First, that’s not true, as the content is in the DOM, so Google can see and index it, but humans can’t.
It indeed it, I think it is not related to cache itself, but to some optimization.
Seems to be related to some DOM-optimization. I would recommend to keep Cloudflare caching your reponse but disabling “Performance” with the same PageRule you enabled cache everything.
EDIT:
I tested it several times with a random querystring (which bypasses cache) and it worked properly. Even after it was cached some requests later. Have a try: Dentures: types and procedure | Authority Dental
Yes, do this. After you can confirm it’s not occuring anymore disable the “Performance Disabled” Rule and just turn off Cloudflares RocketLoader and clear cache again to see if it broke it.