Yeah... it's looking more and more likely that there are either multiple wallet files or multiple seeds... You can't actually select the derivation path when you create a wallet, only when you are restoring it. So, you would not have been able to get a weird derivation path unless you used the seed to restore the wallet before you even attempted to use it.

And you only get to specify the derivation path if you use a BIP39 seed anyway... with an Electrum seed, it is automatically detected.

My guesses are:
- Multiple Seeds
- Multiple wallet files
- File corruption bug

The first one, you'd have to go through all your notes etc and make sure you are 100% using the correct seed and don't have any other seeds recorded anywhere.

The second and third... well, you'd likely need to have access to the drive media and be able to do a file recovery to see if you could recover the original wallet files... which you don't