Prisoner exchanges are a pretty strong motivator for any group, even hardline ones. If the Taliban was up for exchanges I think the IRGC is pretty likely to want to keep prisoners for that too.
I would note ISIS put out some high res, professionally edited video of burning a (Jordanian?) pilot to death while inside a cage. Quite savage, but the propaganda effect is more profound than about anything else I've seen.
Does the US have any prisoners to exchange? Wouldn't we need boots-on-the-ground to capture enemy combatants?