If the rpm droops as he pulls pitch, then doesn't that just mean he was too heavy to hover?
No. he might have had enough power to come gently to an OGE hover. However, he went for the very punchy quickstop arrival (which may well have been downwind) - that needs a shedload more power to stop and is why he then fell out of the sky.
Look at the disc tilt and think about the Total Reaction arrow of thrust the rotor can produce - then tilt it and see how much the vertical component - which is required to oppose weight - reduces.