You can try using a little bit of mineral oil, use a Q-Tip to apply it to the eye and let it sit for a while (I think the advice I got was 8 hours) and then use a damp cloth to wipe it off. If it doesn't come off, it's not the end of the world. If he doesn't lose it the next time he sheds then you can start to worry. You want to be very careful with the eyes because if you accidentally remove the layer that is supposed to be there bad things can happen.