Repair of walls

If it's small you can use wall spackle. If it's large, you'll need to find some sheet goods to fill the hole. Most trailer wall construction is done with a fiber pressboard and covered with vinyl wall covering (wall paper). You may find the same wall covering by contacting a dealer or mfg. but after a few years since manufacture, they don't stock the original wall coverings. You could probably save some time and expense by getting a close match to the wall covering at a place that sells wall paper.

It is most likely not sheet rock. Best bet on a 5-6 year old rig is to think outside the norm for example if in lower 40% of wall can wainscoting and a chair rail cover the boo boo.
If up higher can the entire wall be covered with some nice paneling.

If it's small enough you could put a blank outlet cover over it or hang a pic over it or ?
We bought an otherwie nice TC that had a rather large hole in the ceiling. I installed a white metal vent over it and on one was the wiser.