When I stayed at the RC a couple years ago, I was told that one should phone the hotel and they will have someone (a bellhop) meet you at the airport express Kowloon station to escort you and take care of bags. For the return to the airport express train, just ask.

BTW, the W also offers to have someone help with bags, but they ask that this be arranged/scheduled in advance for departures.

You can also go to the train station early (for departures) to check in and/or drop bags and then return to the station later that day to go to the airport; your ticket (which is required to access the check in desks at the station) is good all day. So you could make a trip to the station in the basement of the mall with the bags to be checked (and your passport of course) and then return to the hotel for your carry on piecs(s).

Also, with the airport disruptions/closures, *do not assume* that you can check in or check bags at Kowloon station, although if you do go to the airport, taking the train without checked bags might be one of the easiest (and less prone to delays) ways right now.