I never used kraken before so Im not sure about the rules. But you mentioned a very huge money, so probably they are being strict on user with kind of deposits like that or from details of your KYC. Better to read vividly their ToS and conditions.
I'm involving an attorney and I will notify the forum users about result here.
Thanks we appreciate for your sharing here. Having an attorney involves is necessary if your asset is something like that. Have you already talk with their support regarding this? Better to settle first with them before doing legal action together with your lawyer.