Originally Posted by Horace

For brands that provide Lounge Access as a benefit to Platinum Elite and above, it only applies the room occupied (and paid for) by the member plus one additional guest also staying in that room. That's clear in the Terms & Conditions.

Hotels can provide benefits above and beyond the published benefits.

You could book a room category that includes lounge access for the other rooms. Hotels with M Club lounges often sell M Club access for guests staying in any room, regardless of Marriott Bonvoy level.

You could also contact hotel management ahead of time making a case that the hotel should go "above and beyond," especially if you have a history of staying at the hotel in the past.