You and your wife are not looking at this correctly. (1) Deeds have been done away with for years and it is only your Registration at the Land Registry which counts now (2) You can check whether the property is Registered by clicking
http://www.landregisteronline.gov.uk/ and following the instructions (3) if it is Unregistered it will now have to be Registered (4) the executor should have transferred ownership into the names of your wife and brother as 50/50 tenants in common (5) ownership by the brother is then achieved by further transferring the property into his sole name. Items (2)(3) and (4) you can do yourself by phoning your local District Land Registry Office and seeking their instructions - you will also have to phone 0845 6030135 and obtain a Stamp Duty Land Tax certificate for the Land Registry. Item (5) will have to be done by and through the brother's mortgage lender, as the lender will at the same time Register a Restriction on the property to secure the loan.