For the towel racks, unless you are lucky and can screw directly into studs (I never get that lucky), you will need to use anchors. Best would be molly bolts. Just make sure you know exactly where you want the racks because molly bolts are a bugger to remove (it can be done without damage, though) and leave a rather noticeable hole. I don't like toggle bolts because they need a larger hole and, if you remove the screw, the toggle drops into the wall.
Mounting the TV could be a bit more challenging, depending on where you want it and how big it is. If the TV isn't too big (say 22" down) and you can center it over a stud, you could get a simple wall mount that can be lag screwed to the single stud. Even stronger would be to mount the TV mount to a finished hardwood board (routing the edges would give it a professional look) and bridge the board over two studs. If you are really lucky, you might even find a place that Jayco reinforced for the purpose of mounting a TV (usually, though, RV manufacturers pick the oddest places for that). If you have to use an extendable mount, you will need to get one designed for RVs that can be locked to the wall when in transit (Mor/ryde makes some) or just figure on having to remove the TV and securing it in a safe place (such as strapped to the bed) when moving the trailer. Because of the added stress from an extendable mount, it would be necessary to span at least two studs with a mounting board.
Whatever you do, don't expect the paneling of an inside wall to support the TV. If an outside wall is 1/2" plywood, you might get a way using 1/4" molly bolts for a simple mount for a really small TV but I would sleep better if the mount was screwed directly to the studs or to a board bridging the studs. It is imperative that you hit the center of the studs. Use an electronic stud finder to find the edges of the stud to determine the center. If the studs are aluminum tube, use molly bolts instead of screws in the studs.