I didn't see it mention he used a climber, nor that he did not have a safety harness on. Either way, I feel climbers are much safer than hang-ons when combined with a good harness. I'm attached to the tree 100% of the time when I use my LW. Not 99%. 100%.
Just a 2' jump down from a set of climbing sticks in 2013 cost me 20 months of miserable plantar faciitis. Ended 40 straight years of running 20 miles/week for me. At 56 I am now struggling to get back in shape from inactivity. Be attached 100.00% of the time. Not worth the risk.
I can relate to that. I simply stumbled and landed on a pointed stump in my side and ribs a little over a year ago. Could not breath at first. This led to back problems I now have. I am your age and I ran too. And I got numbness in my foot. Working my way back. I would recommend you do planks daily as you get back in shape - you really need those stomach and back muscles to run.
As this all relates to stand safety - you don't have to be 50 ft up to get really screwed up!