Does Medicare cover ambulance transfers?

[Blurb]

I don't know for sure, but I know Medicare pretty well, and I would guess in this circumstance they would likely NOT pay for an ambulance transfer. I believe the only reason they pay is if the level of care is required by the patient's condition throughout the time of the transfer, e.g., they require a heart monitor, or to maintain an IV drip, or respiratory assistance/support.

Your sister is correct, and you should take advantage of her gdtr's offer.