What happens if you lose deed poll documents?

[OnBehalfOfSomeone]

Sorry if this is long winded.

Say 'Miss Smith' lives with 'Mr Jones'. Mr Jones owns a house. Miss Smith changes her surname to Jones via deed poll. Then Mr Jones puts Ms/Miss/Mrs Jones on the house deeds. Mr Jones dies, and Ms Jones has lost her deed poll documents - passport etc. is under Miss Smith. What happens with the house? Is it hers? Or because she lost the documents does 'Ms Jones' not exist? Thankyou, sorry if it doesn't make sense!

surely the deed polls are registered somewhere like births and deaths are?

the company that issued the deed poll should have a copy/record of it apparantly.