To my understanding, KYC simply means "Know your customer". Investors(customers) who participate in ICO are made to go through KYC process before they are even allowed to purchase their tokens. On the other hand, Bounty hunters are just "part time workers" of the project and not customers. Even if they will be made to go through a KYC process, it should be before they start working and not after. Waiting for them to finish working for the project and refusing to pay them because they failed to pass KYC afterwards is a total cheat.
I have seen a case where KYC actually helped bounty hunters. So many hunters now use bots to join bounty thereby flooding campaigns with their fake accounts. On a spreadsheet you will see thousands of entries, meanwhile only a few really did the work. In that case, KYC was used to separate the wheat from the chaff.