Hard question: You describe losing calcium in your shoulder joint to the point where the first Doc wants to replace the joint mechanically. And then you had some teeth pulled and that Quack wants to do implants for the missing teeth. In my experience those two things might not go together. Drilling implant holes in a calcium -deficient jaw bone might not be a good idea? Are your two Docs talking to each other as to whether drilling is a good idea? And don’t forget there is at least a few months bedding time after the teeth pulling, assuming the root holes were prepped for implants at the time.
For my own part I’d never mix up root canals and implants in the same mouth. But that’s just me and my observations of others with similar problems. Make sure you understand what the various Quacks are telling you.
They would put cadaver bone in the jaw and let it take for a few months, then drill and prep for implants.