Hey mate, I’m not trying to defend the casino since I don’t have any info about them but according to your conversation with the support/owner, Your casino account is inactive for almost 5 years which means your account already expires. All casino nowadays have this kind of rule in their ToS that ranging from 6 months to 1 year inactivity before your account got restricted.
I think you have the right to claim those referrals that you earn when you are still active but the support has a valid point regarding your existing referrals since your account is already closed. You should read always the ToS so that you will be aware on the casino rules. I agree on the support because I knew exactly that kind of rules exist on any casino.
I also see it that way OP did not play for 5 years his account is already inactive now he just get active and try to claim the referral commissions other casinos would have done the same, OP you are not scammed it's on their terms, that casino does not have an announcement here but this will not qualify in the scam accusation, you just have to move on.
And I'd like to ask why did you not play here since you have referrals that are actively playing.