Kind of answering your question. I was with my wife at the start of her business trip recently at a Marriott in the Bay Area booked via her company's travel agents. My wife has no status, but I was able to apply my Marriott PPE status to the length of her stay since I was there at check-in (I left after the first night). All billing went through her company per the original booking.

Surprising upshot. My account received the 6 nights and 40K points for the stay.