I obviously cannot see what you have signed with DMR and what their terms and conditions were, so I am going to operate under the assumption that the contract with them was legally enforceable and that you had a contractual reason to believe that there was, in fact, no need to make further payments to your mortgage company at the time.
Operating under those assumptions, you would ordinarily be able to recover the amount that you gave to them in its entirety, plus for any damage to your credit, plus any savings or financial benefit that you would have enjoyed under the contract; this would be executed under a legal theory of "breach of contract" and "detrimental reliance". Enforcement would be through the civil courts; if the amount to enforce is $7,500 or less, it could be handled in small claims.
With regard to the refund of $20,455, they might have sent the money to you if you signed, but you would ultimately have had to return to them any amount in excess of what they actually owed to you. It would be a mistake, not a gift, and the courts would not reward you for taking advantage of that.
There are a lot of scams floating around out there right now; I would also recommend that you report their actions to the state attorney general's office to let them know that you may have been defrauded in a remortgaging scheme.
Let me know if I may be of further assistance. Thank you.