In the unedited video we see a tech holding the IV bag up, thus gravity.
I know. That is one reason they said it was fake.
I've never been on a medi-vac plane, but the ward I spend some time in sometimes is on the same level as the hospital's chopper pad. The chopper and hospital have matching equipment, so they roll up the gurney (batteries, O2 bottle etc on it) and the stretcher unit just rolls out onto it. The gurney has roller bearing things on the top, and so has the chopper floor. The chopper section is like a hospital bed (they can raise the head section for instance) but has a raised frame/shelf to hold spare equipment, patient's belongings etc, well clear of the body, and an IV pole of course. The pull the patient out, then swap over everything that's connected to the patient, lock the 2 pieces together, then everyone pushes the gurney inside. The lifts (elevators to Americans) are just opposite.
It takes them about 15 minutes to get someone inside. Then about half an hour later they bring back their equipment and fly off. Usually at least 8 patients are watching, it's the only entertainment in the place. The helicopters are amazingly quiet, and just appear out of nowhere; only way to know there's one coming is by seeing the pad lights on. The hospital people with the gurney don't turn up until it's landed.
On the other end, they need to lift the patient in only if they're picking up from a scene, like a bad crash. Often it's just a transfer from a hospital in a smaller town, that lacks the specialist equipment/doctors.
Nothing in the video looked fake to me.