The Council will only pay if your mother has title - if the property is in husband's name she needs probate to transfer title to her name.
She (or one of her children) can apply personally to the Probate Office for Probate personally - you will need a solicitor for transfer of title after probate - there will be much lower fees but still could add up to c.1.5K by the time all is taken into account - valutions, probate office,land registry, solicitor fee on assent......... .
Another route would be to discuss the lack of title with the C. Council and ask them to cover legal cost of Probate.