Izzy,
Your link shows the conversion of an HDMI output from a source to a legacy composite video and analog stereo output suitable for an older TV/monitor.
I believe that USA1 needs the opposite conversion -- taking the legacy output of the DVD player and making it suitable for a modern TV that has only HDMI inputs. When I updated the electronics in my 2007 Tour Master T40c, I replaced the Sony DVD player/surround unit with a newer Blu-Ray combo Sony model of similar footprint that had HDMI outputs. This did not help the bedroom TV since the chassis wiring in the coach is all composite and not digital, so a small separate HDMI capable player back there solved that issue. See attached image.
If you really need a composite --> HDMI conversion gadget, they are available but are limited to 1080P resolution (not the 4K of true Bu-ray...) Here is a typical one:
https://www.wiredco.com/HDMI-to-Comp...midisplay1.htm
Chuck