Legal aid charge against deceased estate

My Mum passed away in October without a will. She had legal aid for a divorce in the 80s but paid this off around 2011. My sister is handling the sale as I live overseas but there is still a charge against the property which is holdng things up and the buyers are considering pulling out. Is there anything I can do to help speed things up. Mum was also convinced that my late Father owned a 40% share of the property so is there any way that this can also be checked. Hoping for some help.

Lisa - if there's an application currently with us then a request to expedite it can be made https://www.gov.uk/guidance/request-an-expedite

And we don't record the % shares on the register itself. The register will confirm the legal ownership and will also confirm if there's a restriction for example protecting a beneficial share of the type you refer https://www.gov.uk/search-property-information-land-registry

If your sister is selling her conveyancer can assist/advise on the above and will have checked the registered information already