If your coin is 2FA and you never got the first bits, then you currently have no chance at finding out since you don't know the public address.
If your coin is 2FA and you know the address and/or first bits, you can check the balance on any blockchain explorer.
If the coin was graded, they have been known to put the first bits on the slab so you can check it.
In any of those 3, you still can't currently redeem them.

There are different issued coins.  In the beginning, the code on the coin and certificate in no way references the address.
Example...
.1 (Tenth) coins in the beginning were the method that didn't have a code referencing the address.
Serial #   Coin_ID   Bitcoin Address   URL   
6              ZK565hkn  1MAnr5gRn5MTNqn6nTShvjpFUytNSH7S1Y     https://www.titanbtc.com/verify/ZK565hkn
7              v2vV5Tu1   1BdVJYmLvmB83aq78wVP7b6qK4TgLwTAAs    https://www.titanbtc.com/verify/v2vV5TuL   .

The only way to know the address was if you checked previously or had it graded where they put it on the slab.

Then, series 2 coins came out and they started using first bits.  Example...
Serial #   Coin_ID   Bitcoin Address   URL
1              1FBBydqQ  1FBBydqQZTcstttt7EV4f95GNd2LpRYFe6   https://www.titanbtc.com/verify/1FBBydqQ
2              146d2Nrq   146d2NrqBRQyrTkzg7DaVUnTYxsnL4UVwa   https://www.titanbtc.com/verify/146d2Nrq

Good luck.