I have one BP who was neglected, and as a result he has a badly indented eyecap on one side. His former owner did not humidify him enough while he was in shed, and he had horrible sheds as a result. The eyecaps that were retained came off while I had him, and his one eye is still a bit smaller and slightly shriveled, but he still feeds well.
What I would do, is simply wait until his next shed cycle and at that time, UP his humidity inside his cage to over 80%. I know it seems like a bad idea to wait and not take any action, but if the humidity is right the eyecaps should come off with the shed. Also make sure that there is water offered to him daily in his cage. Soaking right now probably will not make much difference and taking tape to his eye could be even more damaging.