This is a little far out there for me…but… what if this is blood testing to determine who is human kek. After seeing that secret service agent, I’m not ruling out the possibility. I’ve been down some rabbit holes, and only a handful have panned out.
You sound like someone with medical knowledge so maybe you might know what applications an IV in that location would indicate. Would it indicate injection of basic fluids? Or possibly something else more exotic? Why the hand?