Article 12 (from the 1993 adoption) of the additional protocols from 1974-1977:
Article 12 — Protection of medical units 1 Medical units shall be respected and protected at all times and shall not be the object of attack. 2 Paragraph 1 shall apply to civilian medical units, provided that they: a) belong to one of the Parties to the conflict; b) are recognized and authorized by the competent authority of one of the Parties to the conflict; or c) are authorized in conformity with Article 9, paragraph 2, of this Protocol or Article 27 of the First Convention. 3 The Parties to the conflict are invited to notify each other of the location of their medical units. The absence of such notification shall not exempt any of the Parties from the obligation to comply with the provisions of paragraph 1. 4 Under no circumstances shall medical units be used in an attempt to shield military objectives from attack. Whenever possible, the Parties to the conflict shall ensure that medical units are so sited that attacks against military objectives do not imperil their safety.
As I read it, it seems very clear it would contravene section 4 there.
EDIT: Actually I’d not call it clear. Because it seems to me they’re talking more about using hospitals and the like to shield military units. But I would argue hiding a unit in an ambulance is a good interpretation too.
The “Interesting” is very Muskesque. I also think if it was DMs to someone else, even in the USA that’s got to be some level of a legal privacy issue.