Is there some way to negotiate final house payments if one spouse dies and (unknown to the other) allowed a policy to lapse?

My mother and father purchased a doublewide mobile home about 18 years ago. There was a separate, required policy that stated if anything happened to either one of them, the house would be paid off. My mother divorced and moved out less than 4 years after the purchase was made. Her name was not removed from the title because my father simply did not have the credit to buy out her half of the house. My father just passed away in early September (with about 2 years left). We just found out that in 2007, he permitted the policy to lapse. My mother was never notified of this (and thus has no opportunity to contact the insurance company and protect herself from just this circumstance). She is now responsible for the balance left on the house and CANNOT afford $500/mo +her own rent.