I understand the challenge with submitting KYC to untrusted platforms but the truth is that the advantages of playing in a casino that request for KYC during registration is higher than those that does not require KYC but might turn around to ask for it when there is heavy winning. That attitude is a sign of irresponsibility wrapped under criminal intentions. There have been countless cases of people losing significant income due to casinos requesting KYC after winning; I consider this a deliberate attempt to steal people's fund.
If you play in good casino you don`t lose your money but lose your time. It is bad, but it is better than losing your money in unknown cheating casino.
I don't understand what you mean by losing time if one play in good casino because definitely time is required to play in casino and I don't consider such time as being lost because it is invested in something worthwhile. What I understand as losing time is when someone engages in activities that does not bring back anything meaningful and casino does not qualify as that because people do win massively.
If it is possible - try to KYC yourself. If casino doesn`t give you such opportunity - you can try to make several small withdrawals. Mostly casino will KYC you. Same time you can check new casino for cheating.
Casinos that ask for KYC after winning generally fo that to cheat because they know that the funds they are performing KYC for came from their platform. Making smaller withdrawals can be a good option but bad casinos will not give that option.