Wish you could explain the collusion and what the bots do. I guess I have seen a similar question in the past with an interesting answer that favours the use of well decentralized system to solve or reduce the problem.
Centralized betting platforms not so transparent, so expect to see such problems.
Any chance you can find that topic you mentioned?
Not sure I can now.
But from the point the poster above (stonerstanl..) made, I guess things could be manipulated if the owner/owners want to. Maybe it won't be that easy for them due to provable fair and other similar feature. I guess the provable is used mostly in Crypto-based betting platforms. .
In my opinion, having a betting platform decentralized will take away the ownership control and potential abuses from one or few "connected" people, and make things more monitored by randomized and anonymous betting community members.
I think a decentralized betting platforms should be:
Well decentralized, Transparent, immutable, anonymous/private, trustless/permissionless, censorship resistant, secure, consensus driven, etc to make them safer and secure from possible abuses by owners/admins