I called the Bonvoy Number and told them that I have a ton of upcoming travel for work -- I have to come to Tel Aviv 5-6 times over the next few months and am staying at a Marriott property. The agent checked the account and saw all of my bookings in the system and granted me a Platinum status match challenge (17 nights over the next 3 months which I should hit). She did not ask for any confirmation or anything from any other hotel programs, though I did say I am interested in Marriott as my main program going forward.