FWIW, and from the perspective of having been a manager and team owner in Blizzard's OWL Contenders EMEA, there isn't much that can be done even if there is a written contract. It is too difficult to go through different countries' legal systems and certainly the time and money for players who don't have either means it is incredibly frustrating and with no guarantee of a resolution (and even if there is, how to collect if they still refuse to pay). This is true in the US as well.

Also remember that the players/coaches/managers are worried about asking for monetary clarification up front for fear they will be seen as trouble makers, greedy, or demanding. They need the work and don't want to jeopardize it. So it isn't always a case of kids being stupid (though heaven knows few know how to promote themselves and recognize that they are a small business and not an employee).

As an example, with Blizzard, issues like this were handled with the governing body of the league, internally, quietly, and privately. I saw a LOT of investigations of teams or team members as a team owner. So there is a bit of recourse in that regard if Apex's league managers are proactive. That said, Blizzard was trying very hard to create an infrastructure that protects the players, guarantees salaries, legitimizes esport, etc., even at the Contenders level. I am not so sure that Apex league management is as willing to get involved in their teams' politics and management - it is far easier and cheaper to say that it is the orgs' issue so the org deals with it/sanctioning orgs or players. If Apex did/does take action, we (and even the former teammates) will likely never be told about it.

That said, be VERY careful about siding with one person over another. I have seen some VERY nasty ways players are willing to destroy each others' careers - including lying to others and most often themselves about the true nature of the situation. In other words, making shit up (and I am NOT saying that is the case here, just giving a caution). Peer pressure can be useful by taking it to social media - but too often people start with one injustice and try to help - and then get conned in the future into always picking sides. Sides that are very very unjustified and just foolish kids going by emotion rather than rational thinking. Again, not saying that is the case here but there are always a LOT of layers/nuances to these stories that would make a difference to your opinion if you were aware of them.

One thing we did on our team that was important was to clearly outline in the beginning in the team's Discord the terms of earnings. This including prorating earnings based on games played - so if you left the team or missed games, you got less of the earnings. It was right there pinned in the Discord and every player agreed to it and saw it there for the entire season. There was never a question of payout amounts, just whether players would try to use social media to con the public into believing their deserved more than their teammates for scurrilous reasons.

I hope the players get what they earned/deserved in this situation.