Since you asked, i just did it on VM. Looking at it's transaction history, 1NUW3z5z6cNs8Ltd2cN2BnxP92dySdcuG8 is the only receiving address. According to mempool.space[3], it has ~3.5BTC. But there's no way to know whether the encrypted part of the wallet is manipulated or not[4].
I do not know how all that .dat files are manipulated, but as far I recall, it was somehow proved that it is possible to "inject" given address into wallet.dat file knowing it's public key. In other words - if you know public key (wallet has spending transaction) it is possible to create a forged wallet file for that address. Wallet will work in bitcoin core, show correct balance etc. But of course it will not be possible to withdraw coins as private key will not be available.
And yes, address from OP's wallet has spending transaction, which means (in my opinion) that chances it is forged change from 50/50 to 99%.