photos cut per mod request
My final sleuthing efforts for this season have revealed Ali's PI's below may have been taped in a Royal Overwater Villa which is the largest villa after the Presidential Villas (MTP). It is possible they are used for LCD private dinners, etc. as well.
I still believe Roberto was probably in one of the Deluxe overwater villas, but I would assume on the opposite pontoon from the Royal overwater villa. If Ali stayed at, or used, the Royal Overwater Villa, I believe the SC of Ali/Roberto bed-serious talk took place in Roberto's villa (LCD) as the Royal Villa bed doesn't match the Deluxe villa bed in the Ali/Roberto SC. The head boards are not designed the same way as shown in photo below. We already know that Chris was in a beach area land villa and we were questioning where Roberto/Ali's SC and Ali's PI's took place. This appears to be pretty close but I still may be wrong. All the SC's will come to life tomorrow night.
PI 1 (Drawn window shades, pillows/couch, plant foilage with some red flowers, curtains, wood paneling)
Royal Overwater Villa living room area: Note window shades, couch, curtains and a similar glass table plant.
Ali would have been sitting closer to the curtain area, at the end of the couch with the table plant directly behind her. She was sitting at an angle to capture the exact PI above, IMO.
PI 2 (Glass panel door on right, window shade, pillows from home?)
Royal Overwater Villa Threshhold between Living Room and Bedroom. Note glass door which is the same as PI 2 above.
Ali may have her back to the bedoom area.
Royal Overwater Villa Bed: Note slats of wood rather than carved headboard
Two Royal Overwater Villa are located at the yellow circles #107 or #126: