I don’t know what the heck I’m doing on this forum exactly, I’m new to all of this, but I have found a viable workaround for the Paramount Plus rewatch issue.
If you use the phone app it is much more forgiving. Select the episode you want to watch and it should reset the episode on your Roku simultaneously or nearly so. You can shut down the app once the TV restarts it’s program from the beginning.
I had turned off auto play but I really don’t think it matters with this particular issue.
This is by no means a fix, Paramount Plus has some work to do but hopefully this will work for the time being. Rock on friends!