Does he have any interest in golf, it's one activity that has continued to give my OH a lot of pleasure and as he got more frail ( he's 86) we gradually reduced from 9 holes to just the putting green, then just a few holes of that. These days we go and watch, and sometimes do 1 or 2 holes, holding onto his walker.
We have used public courses, not the posh clubs, and found one which is very sympathetic to our situation, and even let him take his walker onto the green. Whenhe wanted a lesson to improve his swing, I talked to the pro about his AZ, and he was very willing to try to coach him, saying he could always do it for however long it held his attention, and then just play a few holes with him.
May not be any use in your situation I know but I have been very touched by how helpful they were in trying to help him keep up this interest.
We also played the local crazy golf until very recently.