Getting someone younger to help might be the best answer......except maybe for a potential liability issue.
The only other solution I know is to get two LONG and fairly lightweight poles, tall enough so that one person on either side can pass the end of the cover over the RV while standing on the ground.
Telescoping aluminum poles probably would be the best; easier to store when in the collapsed position.
I'm about to be in a similar situation. A friend sold me a cover he doesn't need and I used the walk-on-roof method the first time. Mine only sits idle about 4 months of the year....in Florida.....where the winters are usually fairly dry and mild (but as I type this there is a severe storm watch out).
I may just sell it.