My 2011 Georgetown 327DS had a similar cabinet already installed for a tube television, with the cabinet a dead space behind a panel that matched the woodwork. The front facing of the cabinet was doubled up, allowing two different size televisions to be installed without having a large gap around the tv. I removed the inner facing pieces and used them as a template to build a replacement frame that holds the flat panel tv. Mine is hinged on the left side with a piano hinge and I used a knob with a long bolt on the inside that has an arm at the head of the bolt that can be rotated (with the knob) to catch behind the remaining facing. This is a positive lock for the swinging frame and it's never come loose while driving.
I showed this to the FR folks at the international rally after I installed it and they made notes which I hoped they would use for future models. Newer models had the cabinet recessed, eliminating the storage behind the tv, limiting the size of the tv, and moving the light under the cabinet to a location where it provided less light to the floor at the foot of the bed. Overall, not a good design improvement.