Yes I think also that you could leave the baggage at a bell stand at a hotel regardless of whether you are staying, status, etc. If they do for whatever reason bring up "are you a guest today," etc., then you can just say that while you are not a guest today you are a very frequent guest i.e. your diamond status. I don't think you'll have a problem, but of course, get some kind of claim check that they do have your bags just in case when you arrive to pick them up nobody has heard of your luggage, you, etc.