For the golfer's elbow, you might try what Mark Rippetoe recommends here:
Basically, do a lot of sets of bodyweight chinups with a submaximal number of reps. In the second video he recommends each set should be a third of your max. E.g. if you can do ten reps, then he suggests sets of 3 reps with a 1 minute break, with the goal to do twenty sets (but if it is too painful, then start with fewer sets and work up).
It seemed to work for me. I developed golfer's elbow just before the last time gyms were forced to close. It didn't seem to go away even when I was just doing some bodyweight stuff at home, so I tried the protocol he recommended, and it seemed to work (at least I no longer have golfer's elbow).