honestly why would someone KYC in a casino that is already leaving? the casino can sell people's documents, the casino is not licensed, so why are asking for KYC? if they're leaving what's the point of asking for KYC, where is he going to keep these documents? i hope people don't fall for scam, people's documents is something very important and shouldn't be handing over anonymous people and in a place that is being closed
Perhaps they really wanted to get back their money at whatever cost. 1700 Euros isn't a small amount so the person was caught between losing the amount or giving it a try by sending KYC documents.
There are some sites that I would personally never sign up for and play in, just in case they asked for KYC after I have won a huge amount. GXGbet is one of them. At least I would be comfortable with the old, trustworthy casinos.