But, I will like to know if there can be any way someone can check the validity of his paper wallet private key correponding to his address.

You can simply install Electrum on an air-gapped computer, import your private keys and check generated addresses.

This is good practice to do. I always check if I can recreate an address before funding a private key that wasn't created by a wallet.

There must be a glitch in bitaddress.org when doing it offline.

Are you sure you downloaded it from the original website? One character difference could lead to phishing.

I then tried the same thing use £2 on the saved webpage version of Bitaddress.org and the private key does not match the address it was sent to

Can you email (LoyceValenzuela@gmail.com) me the (compressed) version you downloaded? I'd like to compare it to the original.