Make your KYC policies clear. So that we know what type of documents are needed with respect to different countries. Either you say that you do not need KYC documents at all or you demand them right at the moment of signup (before user's first bet).
Nowadays it is a common trap which crypto-casinos using to avoid big payouts.
Don't give us bullshit like 'whenever you feel security compromise you need document verification otherwise not'.
MAKE IT CLEAR, YOU NEED DOCUMENTS OR NOT !!! and if you are bold enough to admit that you need documents (as per rules), publish the list of documents with respect to countries.