This is pretty much what you would see, I have dealt with a hemipenial prolaspe with a chuckwalla, thankfully I got it to go back in, could not get a vet over the weekend.
But if I were you I would call the vet as soon as possible, and in the meantime until you get him there, you can try soaking him in coolish sugar water, and keeping it moist back there with KY- jelly.
You said you can not handle him, I would atleast squirt the KY- Jelly on his vent area.
Works awesome, if it is a prolapse of any kind it must stay moist, if it dries , the tissue usually dies.
Call your Vet, and let us know how he does.
Prolaspe photos
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PHEve / Eve
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