You shouldn't be surprised at all.
I cant understand why the sepa transfers wouldn't work from revolut to kraken.
Continuing to block the money flow, would be a joke.
There are KYC for both kraken and revolut, so frauds are limited if not eliminated.
Why that? Since Kraken doesn't accept deposits coming from Revolut (source link posted above by @gentleman)
As a security matter, Kraken is also blocking any deposit coming from some traditional banks (and all banks have KYC procedures) so nope, frauds are not limited or wiped out
I mean kraken is here to make profit.
So it would be stupid for them to continue block customers money because of some ridiculous reasons.
If i am required to verify myself both on kraken and revolut (like everywhere else as you say) i cant understand how one can "fraud" them and damage their company.