I've done it on travel trailers. All you need is two bases (the cups), one mounts under the table and the other mounts on, or in the floor, and the pole / tube sections at the heights you want.
The Slide Out Floor: Be careful where you mount the base on the floor, you don't want to hit anything under it. Since your dinette is on a slide out you may be able to use a recessed base that mounts flush with the floor. Measure the distance between the slide floor and the real floor to see if you have enough clearance with the slide retracted. If not you can still use the non-recessed style cup that just screws to the floor.
The Table: Before mounting the base on the underside of the table you may want to glue a piece of wood on it first. A piece of 1/2 inch plywood 8"X8" centered on the table bottom should do the trick. That gives you more depth for the screws holding the base to the table top. Make sure the screws you use are short enough they won't poke through the table top.
Since the "R" offers an optional couch and pedestal table, in lieu of the dinette, you should have plenty of room to mount the table.
My local dealer and Camping World stock all the parts you need. This should be around a $20-30 modification.
2017 Sunseeker GTS 2800 QSF
TOAD: 2016 Ford Edge Titanium FWD