Happy to look into this for you, 7!
Stay tuned. I'll follow up with what I find out.
Hey 7! By virtual concierge, do you mean the mobile app? Points can only be earned if you book through Marriott. Booking through a third party service will not earn points. Hope that helps! Let me know if you are still looking for answers.
No, it is not an app. A few days prior to a stay I usually receive an email with a subject like "Your upcoming stay" confirming the details and with links to things to do and often another section titled Virtual Concierge. Clicking on Virtual Concierge takes you to a page on vc.stayatmarriott.com and then you can buy a room upgrade, book transportation, request room service items to be waiting for you, and enter other requests.
It seems like it is through the hotel, so I assume the charges will be billed to my room and would earn points. I already booked the airport pick-up, so I'll find out tomorrow for sure and report back.