After they receive the KYC does anybody think they will just file them away and forget about them? No. They will sell them on to make more money.
I don't understand why anyone would feel like providing their KYC to 1xbit where it's not even safe to invest money. Scamming money and selling KYC is basically a double blow for the victims.
I don't think they have a security team honestly speaking. They will keep providing various excuses and most probably use these excuses to not resolve your issue.