Burden of proof in estate recovery

I have a friend with a £15,000 op demand for his late mums estate.  She went into care and he’s pretty sure he told the department (he was appointee).  They have no recordings of calls but say he didn’t inform them.  What are his chances at appeal?

Could he provide proof he called? Phone bill/statement?

He’s looking thorough records, but has found a letter to the AA department asking, rather hopelessly, for an increase in the level of AA as his mother has entered a care home.

This is useful but is it going to count as disclosure to PC?

As an update, we won.  However the judge did say that although he was persuaded by my ‘interesting’ argument he rather thought the department might appeal.

Brill :) Fingers crossed they don’t.

They"ve decided not to appeal. Good news in most ways but it might have been a useful precedent