(apparently i wrote too much so i have to split it in two. whoops!)
but that all being said, if i were to be honest, i think the biggest reason brawl stars hasnt taken off is something that isnt really because of anything on your end. its the same reason that the once thriving mafia board is completely dead, and why we typically only do one Killing Game a year, and thats just the main level of activity on this board. the heyday of the boards where we had 5 games of mafia with 20+ players all occurring at the same time, with another 5 waiting in the wings to be able to start, is long since gone, and it seems that more freeform RP has mostly taken it's place... and to be honest, the whole forum isnt as active as it used to be. so even if brawl stars had been a perfectly planned and presented and balanced game, its still possible - nay, likely - that you might've gotten the same level if response anyway.
i said a lot of words here (its one of my specialties), but i hope you can find some food for thought in here. again, i dont think the idea is inherently bad; there's definitely some potential in here, and you just need to think through the format again and a few of those other things, assuming you'd like to try again. if so, i'd recommend that you dive into the glitz pit and take a bit of a look at some mafia games from there, as well as check the awards boards for some of the Killing Games, so you can get an idea of how similar games to this one work. but, dont be afraid to break out of that mold, either! i'm just speaking from my perspective as a long-time mafia and killing game player and seeing the potential influence those games could have to make things better, but someone who primarily does the freeform RP found in the roleplay board will have a different, and perhaps equally valid, perspective on what they think is important, and thats something you should consider too, especially since they will probably be your target audience.
but that all being said, if i were to be honest, i think the biggest reason brawl stars hasnt taken off is something that isnt really because of anything on your end. its the same reason that the once thriving mafia board is completely dead, and why we typically only do one Killing Game a year, and thats just the main level of activity on this board. the heyday of the boards where we had 5 games of mafia with 20+ players all occurring at the same time, with another 5 waiting in the wings to be able to start, is long since gone, and it seems that more freeform RP has mostly taken it's place... and to be honest, the whole forum isnt as active as it used to be. so even if brawl stars had been a perfectly planned and presented and balanced game, its still possible - nay, likely - that you might've gotten the same level if response anyway.
i said a lot of words here (its one of my specialties), but i hope you can find some food for thought in here. again, i dont think the idea is inherently bad; there's definitely some potential in here, and you just need to think through the format again and a few of those other things, assuming you'd like to try again. if so, i'd recommend that you dive into the glitz pit and take a bit of a look at some mafia games from there, as well as check the awards boards for some of the Killing Games, so you can get an idea of how similar games to this one work. but, dont be afraid to break out of that mold, either! i'm just speaking from my perspective as a long-time mafia and killing game player and seeing the potential influence those games could have to make things better, but someone who primarily does the freeform RP found in the roleplay board will have a different, and perhaps equally valid, perspective on what they think is important, and thats something you should consider too, especially since they will probably be your target audience.
i think the most important issue to address with the game is that its hard to grasp what it actually is. you've put it in the Roleplay board, which isn't necessarily wrong since it definitely has elements of RP in it, but i would say that, due to the amount of structure that the game has, it probably has a better home in the Glitz Pit, since in some ways it's similar to games like mafia or KG (more on that later). so to start with, that's may be either alienating people who are RP board regulars due to the added complexity or making people just miss it because theres just so many games in that board
looking at your opening post, theres a whole bunch of rules and modes and characters there, which can be a daunting investment to immediately jump into, but i'm not really sure how much of this is even immediately relevant or purposeful. i understand that it will become relevant once the game theoretically gets off the ground, but having so much stuff out there from the word go, when you'll only be doing one mode at a time can, again, make things seem a bit more confusing than it needs to be.
looking at mafia and KG, although there are a lot of shared elements, such as characters, maps and "game rules" (in the case of Brawl Stars, this would be your different Modes and their accompanying rulesets), mafia and KG manage to simplify things and make it more digestible just by adding a bit more structure. for instance, like Brawl Stars, there are always several roles/characters that appear in each game, but the full list is never posted outright and the roles are all assigned by the host beforehand, which both makes it less daunting for players signing up and also helps make a more balanced game. similarly, while most mafia and KGs have their own variations and different rules (and KGs having different maps for each game), each game gets its own signup thread and only has the rules that apply to that one specific game, which makes it a whole lot easier to understand what you're getting into when you sign up.
now, at this point i'll say that you don't need to be like mafia and killing game. i dont think it's necessarily a bad thing to be a little more freeform or to let people choose their own roles - in fact, i think it's quite an interesting idea - but if you can work at making things a little easier to understand, that might make it a little easier for people to engage with it
the other major point i'd like to bring up that ive noticed is that, after reading through the thread of the actual Tourney, the game itself feels... well, with no offense intended, a little dull? i appreciate the effort in your writing to make it feel like you were giving exciting commentary of what was happening, and i understand a need to make sure that you're not giving away what the other players are doing publicly, but as someone who was not a player sending in actions and is now reading through the thread, it just doesnt seem that interesting to me? i know that the other people are playing in PM, but since the majority of the action is happening there, i dont feel like i can look back at the thread and enjoy the game to the same level as a spectator as someone playing did, which i think is an important thing to have, particularly as a forum game. otherwise, whats the point of having it in a public forum thread in the first place? i'm not sure if youve noticed, but the Killing Game this year was a big thing, and for many of us, whether we were playing or not, it will remain a cultural hallmark on this forum and is something that people will be able to enjoy for years to come, because its been made in a format which is easy to read, and while technically half of the game's phases are conducted by PM (the night phase), everything that happens during said phase is used to impact and is typically revealed during the day phase, which is where the real meat of the game is actually played. conducting a game solely by PM with the host being the only one to ever post just doesnt seem as inherently interesting as a game where you are directly interacting with a bunch of other people in a public format that can be read and reread as many times as you like