Super late here but I used to suffer from tennis elbow pretty bad when I used to rock climb heavily. Some of it was caused by bad form in certain areas. And the rest was just the difficulty in the routes I was climbing. I still. Have it kinda today. But it’s not as near as bad. My elbows snap and pop all over the place, so loud you can hear them from across a room lol.
Anyway I started massaging the nerve bundles on my forearms and bought a device called an “Armaid” it’s made specifically so you can massage the forearms and gets rid of tendon pain. My nerve bundles there where the tendons come together would develop like a big knot around the tendons causing me pain. But when you get in there and massage the knot out. And I’ll say it’s pretty painful to get the knot out…. It definitely hurts and you have to man up and do it and don’t tense up and breathe. Once you break it up you’ll notice a few minutes later your range of motion improves and your elbow won’t have the pain in the back of it anymore. Look up Armaid, they are like 60-80 bucks but they really work great I’ve turned lots of people on to them. I won’t go climbing without it anymore.