For "the real thing" if there was any question about the ILB crew's competency the helo crew would ask them to stop engines, deploy their sea anchor and treat it like a dinghy. Simples.
Except, as I'm sure you know, that is far from simples as the downwash causes all sorts of problems and the run-in has to be quite fast and precise.
As for the role demo - RNLI crew inexperience doesn't answer why the winchman was 'bounced' horizontally into and out of the IRB - looks like a good way to pick up a back injury to me.
If they sit beneath the aircraft door, how will you get the winchman to the IRB since he will be behind the 'underhead' due to wind drag?