Salvage A Save File

Was playing Italy in 1941. Took pact of steel focus and didnt want to. So I tried to edit the save file to remove the line and replace it with the rome protocols. When I try to load the file the date is wrong as well as the difficulty, and says its a different game version and cant be loaded.

Ive since found out that opening them in a text document can mess them up. Eventhough I saved a backup before I did any of this, its saved as a text file and not a hoi4 file, so it doesnt appear in the load list.

Anyways, is there any way to salvage it or do I have to load back in 1939.