Hard to say what caused it, but possibly the superworm did get him. If you keep it clean it should heal. I would have a vet check the eye with a scope to determine if the eye itself was injured or not. If it was the eyelid, using a topical antibiotic such as Polysporin (OTC from any grocery or drug store) should be enough. If it is the eye, you may need some optical antibiotic ointment such as Terramycin to protect it, make him more comfortable, and prevent infection.