Can different coax be used: YES
Should different coax be used.. In most cases YES..
Logic follows
Most (All) RV's the Park Cable jack runs to multi-function device, one function of which is a SWITCH, This will either be a box with several switches (Matrix Switch, Box of Many Buttons, BOMB) or a wall plate.. Many call it "The antenna booster" In most cases that is NOT one of it's functions, but providing power to the booster is (The booster is part of the Antenna itself)
If you have a SENSOR pro.. Well that's the exception, it is a booster.
You must disconnect from this device to use it for SAT (NOTE: the CABLE port on the switch is a good place to feed the TO TV Coax from the Receiver.... if that is there is such a port on the receiver.
Of course the means you need to re-connect it if you are in a park, like the one I'm in, with cable.
Too much work
Plus this is often lowest bidder RG-59.. Very high loss.
Some RVs.. Well Some have a dedicated SAT cable, This cable runs straight from a connector on the outside (or in a compartment) marked "SAT" to either a wall plate with like marking or a cable end hopefully with like marking in the electronics area.
However again, this cable may be lowest bidder RG-59.. but if you got one, check it out.
You shoudl run QUALITY RG-6 to either a drill your own hole jack or if you wish there are ways to get out into the exterior bays without drilling.. If you do that and can find a nice metal bracket install a Ground Block
When I got MY RV I put in a roof top antenna, and a pair of A/B Switches
A: for the roof top antenna up A-Bove
B: for the ground B-lock which was mounted on the B-Rake B-ell crank B-racket down B-elow under the B-onnet (hood in the US but the real English word works better for this post)