deceased exhusband never quit claimed property after divorce

i was divorced several years ago and awarded the house. my exhusband was supposed to quit claim, but didn't. he asked me if he could do a refinance to help his credit (after the divorce). he said he would quit claim it after the refinance and make half the payments, so i said okay after i asked the broker if i would have full access to the loan since the payment would come out of my account. the broker said yes i would! my ex supposedly gave them a copy of our divorce decree in these proceedings( which would have shown that i was awarded ownership)it was processed. then the lender quickly sold the loan to another company. when i tried to talk to the new company they said they had no paperwork with my signature anywhere(i signed papers). then my exhusband got leukemia. he asked the company how to add my name. they told him to fax a request letter. he did so three times. they claimed they never got it. he died. they won't speak to me, even though i am the legal owner of the house. what do i do now?