I really don't know the reason why they forced me to do KYC. Right after I requested a $300 withdrawal for the first time, a forced KYC link popped up.
Luckily, I was able to provide all the required documents. And yes they also asked for proof of address, which is yeah I struggled with at first.
Fortunately, I had a credit card billing statement with my address, and that successfully verified my account.
I hope I win that multiplier contest, and I'll try to withdraw the winnings to see if the withdrawal will be instant this time.
I guess I will have to wait until I sort out the proof of address part. I don't want to win something, request for a withdrawal, and then I have to labour to have my KYC verification done as quickly as possible

Perhaps the trigger was because yours was still a new account? Mine is old.