Yup and I think they're admission was based on the belief they are immune. Ron Paul tried to repeal that immunity with a Traveler's Dignity Act or something a few years ago. It failed to pass...
https://www.govtrack.us/congress/bills/111/hr6416
But what is also interesting (to me) is I could not find the specific law(s) that permitted TSA junk checking. Plenty of decisions on the how the Fourth Amendment does not protect us from groping when deemed reasonable. Making it a game to check out "cute guys" obviously isn't reasonable. But I couldn't find anything that elevated that to a crime.
I think you'll see this story die a quick death with no charges. I'm actually really surprised it was reported in the first place. Gov doesn't like to admit to its over-reach(around).
In a perfect world we have real homeland security--no need for DHS.