I'm not saying they are exploiting anything, but to answer your question.. Noone has the balls in this scene to actually provide any concrete evidence on anything, and when shit hits the fan it's always privately settled and vanishes into a memory.
Apart from cases that are beyond saving (eg. Kqly, forsaken etc)
If anyone from the top teams was proved cheating, it would hurt the scene more than it would hurt the player. Yes he wouldn't be able to play competitively again for awhile, and he'd have the stigma around him - but the game would be ruined. If someonr got away with cheating in the top circuit, other people must've known too.. And from there it would spiral out of control. The amount these people spend together is unreal, there is literally no way their teammates wouldn't know or at least suspect if not paying much attention.