We recently installed a 19" Jensen JE1912 purchased on eBay in the bedroom of our 2500TS. Our unit is similar to your model except for the slides. Unfortunately, I don't have pictures.
I mounted a Master Mounts articulating TV mount that locks to the wall for travel. It is a very strong, well designed, well made mount. Master Mount Locking Cantilever Mount, Small - McNaughton 94139 - TV Accessories - Camping World
To do a clean mount, I removed the 12 volt/cable wall receptacle and move it aside. Using an aluminum yard stick (tape measure will work), I slipped it upward inside the wall and flexing it toward me inside the wall panel until it bumped the backer board. I took that measurement at the receptacle cut-out hole. I then used this measurement on the outside of the wall and marked it with masking tape. I knew this was the bottom of the backer board. Using that mark, I measured down from the ceiling, moved to the point I wanted to place the mount and marked it with masking tape. Using a flashlight and DW's compact mirror, I looked inside the wall to make sure I would not damage any wiring.
Using #8 x 1 1/4" wood screws, I attached the swivel mount above the masking tape mark, solidly attaching it to the backer board. You can not
use a level unless you are absolutely certain the camper is level. I did a measure from the outside wall to the screw holes.
I then placed a household electrical wall plate (for a coax cable connection) with a single hole in the center to mark where a half inch hole through the wall is drilled. A piece of masking tape on the bit as a depth gauge was used so as not to drill through the opposing wall panel. (Though there is a retrofit 2"x4" box for low voltage mounting made for this purpose, I felt that cutting a large hole would weaken the backer board.)
On the plastic wall plate, I drilled a second 3/8" hole just above the center hole. The plastic plate was painted to match the TV mount. From the front of the plate, feeding a coax cable through the center hole and the 12V power supply power cable through the 2nd hole, I fished the wires through the 1/2" hole back inside to the factory 12v/coax hole, then attached the plate at the TV mount to the wall with small wood screws. The TV 12v line was spliced to the RV system behind the cigarette lighter. The coax was removed from the factory plate and a coupler was used to connect the factory coax run directly to the TV coax extension. Once tested, the factory 12v/coax receptacle was re-installed.
I made certain that the wires coming from the wall at the mount to the TV fully followed the articulating features of the mount, had enough length to allow for the TV connections and then zip tied them to the mount. The 12v cigarette lighter still functions at the wall plate. The coax at that point is now inactive. The TV 12v feed has an accessible fuse just behind the TV. There are no wires showing or hanging down. We have used it several times and it looks great and works perfectly. This would work exceptionally well for you with the corner bed. Hope this helps.
If you are at all handy, this is not difficult. I was a little apprehensive at first, but once I started, it was a piece of cake. The hardest part was feeding the wires which was really not that hard. Because the mount will be more to the inside corner from the 12v/coax opening, you can use a coat hanger or 12-14ga electrical wire to make a "hook" to catch the wires to the opening. Or, you can feed a piece of string inside the wall from one point to the other. Fish tape? Better yet. Make sure you have polarity. The hot lead at the cigarette lighter is at the bottom. The ground is on the side (barrel). Just think McGiver!