Well, ofc you cannot know if the private key correctly corresponds with the public key (QR code on coin) - however there are no known cases of this not being the case.
So you could just scan the QR code and enter the displayed public address into a Bitcoin block explorer, for example: https://blockchair.com/
You would see if there are still "spendable output(s)" available with your balance or if these are swiped. If the explorer cannot find the address it means it was never loaded and thus cannot be found on the blockchain.
All that said, for now I believe there are no known issues with private-key Titan bits.