I know that in most situations if a person dies owing money then than debt does not "die" with them but becomes a liability on their estate.
I'd be interested to know what happens if a sum of money is owed to a person who dies before the money(which, in this case, is a loan repayment on which the borrower is showing signs of defaulting)is repaid. I know when my father died there were small amounts owing to him from various sources and they were paid into his estate.
Presumably ANYTHING owed to the deceased forms part of their estate and can be claimed by the executor(s) of the deceased.