Yes, "get a rise out of" means to aggravate or provoke the TSA agents, to get a reaction from them.
"Junk" in this instance refers to the male genitalia.
And I agree, it is very much a mess and, in my opinion, an uncessary one. It is called security "theater" for a reason - it simply gives passengers the illusion that the FAA is doing all this to ensure safer flights. In the US, at least, the TSA employees are not selected from a pool of highly trained security professionals. Sadly, many have credentials that would barely make them employable at any given fast food restaurant. This is why we now have stories of TSA agents keeping and ciruclating the full-body scans of passengers among themselves for sophomoric titillating purposes. Something the traveling public was told would never happen....
Interested in Language