The rim bothers me enough that I would not only have not given it a CAC bean, I would have details graded the coin, as AU details. To me, it is not just a rim ding, but an actual dent. Talk about market grading at its peak!
I'm very picky about 3rd side damage also & have found that JA is not. My guess is anything a prong can hide, he leaves that judgement to the TPGs. Perhaps this is because he knows he can never see all of the edge in slabbed coins. This is also why I prefer PCGS clear pronged gasket holders over NGC & will only buy a "pig in a poke" with a huge amount of skepticism.
Rim Ding + obverse full of hairlines = AU Details Sorry, I‘m a Bit harsh, but every 20th Century gold coin would earn a Details grade. There should be obviously no difference in grading coins of another Century.