I don't have advice but didn't want to read and run. Maybe ask for physio to ease his rigidity if that is the main problem because that should remove the obstacle to try again. Also speak to the main person at the home and get them to formulate a proper plan.
My Mum is unable to walk any more and she absolutely hates the hoisting. I can't fault her care home as they are doing their level best to try to help her stand again just enough to get into her wheelchair. However, some of the carers do not have the strength to help her so sometimes she just has to be hoisted. I have accepted that because it is their backs waiting to be injured if they aren't strong enough to help lift her to her feet.