You can only submit grace deletion requests for domains you register in your Dynadot account. If a domain is moved into your account from another Dynadot account, you will not be able to submit a grace deletion request for that domain.
It does not matter if the domain was registered in another account, then grace deleted, and then registered again in a different Dynadot account.
If your domain was registered in another Dynadot account and was then moved to your account, you will not be able to submit a grace period deletion request for the domain. The domain must be in the account in which it was originally registered before it can be grace deleted.
We do not offer refunds for grace period deletion requests. We only offer account credit.