Dave J -- Is your wife on traditional Medicare with supplement (that is, not a Medicare Advantage plan?) If so, does she meet the home health criteria mentioned above?
She is on Traditional Medicare and supplement G. She has the shot in Doctor's office, they get it no problem for her, she does not meet home health care and has not had a fracture. She has had it 3 times , so far, since going on Medicare. Next time is in November. Her doctor is a busy OBGYN. They have paid every time with zero problems. I think the nurse calls a week or so ahead to make sure she is coming to appointment , likely to verify before ordering drug, but don't know that. There are other injectable drugs for same condition that have to be taken 1 time a day. My wife was on one of those 10 years or so ago. For two years she self administered. I'd guess they don't want to pay for a home health nurse to give those daily unless you are really unable to give it to yourself. a daily visit to home would be expensive.
If your Doctor is in a practice with enough patients to have a dedicated Medicare billing clerk, maybe they would be a good source of info on payments. I commend you for researching before hand. It is confusing. Good luck.
Dave