VIN can be found on your lending agreement. Also if you download latest app, should be visible under Settings > Notifications > Vehicles (may be different for iOS)
Lastly, you can find it on your account page (done on pc/laptop), right click on page > view page source > search for VIN, should begin with LRW.
My SA literally ghosted me after I gave him my RN. Before I actually ordered, in our email conversations, he kept reminding me to give him the RN when I ordered so he could "keep me up to date" on the progress of my order. Tbh, I don't know if the text messages I've received (allocation, and delivery texts) are from him or automated.
I did email him after my order to ask him about the wrapping company he recommended when I was in store, but I never got a reply so...
He did help with arranging a test drive, answered a few questions I had. But I was always planning to get the M3, so I would have ordered with or without his input.