"If they take too long I'm sure we'd all love to see any reports. I've had my suspicions in cash when 4 or so new (less than 10k hands) players enter a table similar times and all have 30/13 stats or so, and all make tank-bluff catches on rivers with mixed or even bad bluff-catches (card sharing)? But I could just be paranoid lol."

Well they do this extremly obvious considering the same stats and entering the tables in a spawn of 5 minutes for months now, paying to see whole cards helps regulars understand this type of collusion, we can easily identify the blockers and the logic behind some unortodox plays, they don't do the obvious bluffs like when someone has the flush blocker but they donk or check raise in 3bet pots or 4bet pots when one of them has the top pair blocker or set blockers so it is not easy to prove the collusion, but 99% of the regs on the platform have a pfr higher than 14 at that stake so 4 players on the same table with pfr 12 or 13 is a big red flag . I think they are bots or have some sort of automatisation because those stats never change on all accounts and they take actions in less than 2 seconds. It is highly unusual for a player to have the same stats for under 10k hands. I had tens of accounts on different platforms and my stats always change with the games and gameplay.

I also saw them lose huge to some 5th player with fish stats 40 15 or so, maybe they just chip dump so they do not atract any red flags to the system and the 5th guy takes the winnings, considering they are breakevenish they do not crush the games, just make it very hard and requires more vigilence to play against , but this is just a supposition can't have any solid proof for that. The team has to investigate 30+ accounts that i sent to them and i will continue to do so as long as they are in the games.

That said, having all the information behind should be easy to prove the collusion, considering i can prove it just by playing for a month at the tables against them and paying to see their cards in weird spots. All the patterns that i described in the posts above and all the hands i have paid to see should be enough for a case.