That's what the missing stay team do. I'm a little confused by your experience: you contacted Customer Support first, instead of the missing stay team, and after contacting Customer Support, your stay was added to your account in a partially complete state (nights but no spend)? If I had to guess, by contacting Customer Support, you unintentionally circumvented the missing stay process. A missing stay typically means a mistake on the hotel's part, and the missing stay team rectify that based on your submission to them (which would include validating information provided by the hotel). That said, I have always assumed if someone were to call Marriott about a missing stay then they would be told to submit the missing stay form instead, so maybe something went wrong in the process, maybe a Marriott employee went off piste for some reason.

Anyway, to answer your original question: Marriott is a huge company with a high volume of customer support, their focus is quantity over quality, so almost every common scenario is well defined, with templated emails and information that customer support agents are sticking to. If your customer support need goes outside the bounds of what is well defined, then it's quite possible to have a frustrating experience. I'm still not sure how exactly you ended up in this situation, because missing stays are perhaps the most common issue Marriott deal with and they have a very well defined process with it but that's neither here nor there.

You can contact the Marriott Bonvoy representative on this website (Marriott Bonvoy Lurker II) or send an email to [email protected].