after reinstalling windows, the probability of getting a wallet is extremely small
Thats not true at all.
Windows uses how much? About 20-30 gb?
After reinstalling windows you have a 25/1000 (= 2,5%) chance of your file being overwritten (assuming 1 TB hard drive) => 97,5% chance it still exists.
Thats just a theoretical way of calculating the probability.
But files are most probable NOT lost after reinstalling windows.
The more you are using your PC the less probable it will get to retrieve an old (deleted) file.
I did a format on my old pc back in 2012/13.
5-6 years is quite a lot.
Did you use the hard drive frequently? Chances are pretty small you will find your wallet file after so much time.
Is there a way this wallet is not called wallet.dat and i need to check some other files?
You may have renamed it?
The file extension for wallet files from core/QT is .dat.
You might try to search for
*.dat. This should give you all .dat files (not only those which are exactly named 'wallet.dat').