I've never heard of "air baths" for mystery snails. Mine lived in a rimless tank & would sometimes climb out. Probably looking to lay eggs. They would hit the wood floor with a ping pong ball thunk. I would rescue them. A few times I didn't notice for a while & their "trapdoor" was closed tight to keep them from drying out. They were fine after I put them back.
They have a siphon that they can use to breathe atmospheric air if they want. I never saw mine do that. After all the "jumpers" I left their water level down a couple inches, it helped a little bit. A self-administered air bath? LOL
I'm not sure how that would "rejuvenate" them. I did a very brief search & saw how to do it. But not why (shrug) If you try it be, gentle detaching them from tank or decor, you don't want to hurt them. If you tap lightly on their shell they may retract. I'm not big on handling my "wet pets" often.