Yes, the Gazebo is on the Tulum side (for sure, I don't know about one on the Akumal side but I still have two weeks until my wedding), and yes, guests can stay at either the Tulum, Coba, or Akumal side (I had my TA check), but it isn't really recommended b/c from what my TA says, they're not exactly close walking distance and it will be harder for them to keep with the group...but if it's a last resort it would work.