W don't get very much help on drawings for trailers, but some guessing on what is "normal" may help. There are often connections for cable that have some coax outside or in a compartment, then there is almost always a connection that can lead to an outside antenna.
That is where the small button on the faceplate and LED often come in as the tiny switch turns on an amp and changes the feed from cable to OTA.
But for coax feeds to the TV, there is often a coax brought from each TV to a "splitter which acts like a tee feeding signal from one source to all the TV.
But what makes things hard is that there are many ways to wire and many folks who change what was first installed! That makes a tone system really handy as you can attach the tone on one coax and go around to each place where you find a coax end and see if the tone shows up there!
One way to maybe cut the chase a small amount is to unscrew the faceplates and pull on the coax wire to see if there might be a splitter right behind the faceplate and "sometimes" you can look/ feel if the wire goes up, down, or sideways as a hint of where it might wind up.
A really super tool is one that you can trace the tone signal, even through the wall, but those also cost a bit more!
A guy using a tracer, may give some ideas: