Have you tried to use "-salvagewallet"?
You can try that to save your corrupted wallet.dat file. You can do it through a command prompt under the Bitcoin core folder to run "-salvagewallet"

or make a bat file for this with this code inside
put this bat file to the bitcoin core folder then run it.

You can follow the guide on how to salvage the wallet file from here https://www.youtube.com/watch?v=exzfi1OKWow