Missing middle name of deceased joint owner on title deed for remortgage

I am remortgaging a house that I owned jointly with my late husband. Unfortunately he didn't use his middle name on the deed and had removed it from his passport and so the conveyancer wouldn't accept it. My probate has also known as with both versions of his name on it and it was used to transfer other property into my name. I just want to clarify that a probate with both versions of his name are accepted by land registry as they conveyancer wants me to change the deed into my name. I am also anxious to get this sorted ASAP.

Liza - it's very much up to the lender and the conveyancer as to what they will accept in such cases. And whether they need the register to be updated before the remortgage goes through.
There are cases where we can for example accept confirmation from a conveyancer that the named individual is one and the same for registration purposes and we can make an entry to that effect. 
If there's an issue around it then I would suggest making an application to update the register re the legal name and providing the appropriate supporting evidence to confirm that for example passport/driving licence.
Once submitted the conveyancer can request expedition to get it processed asap to enable the remortgage to proceed