You asked where to find the pump.
Since it's not running, you'll need to use your intuition. With it running, follow the noise.
Starting with noise, have you ever heard it running? If so, that's a clue to where it is.
Possible locations:
~ Under a seat in the dinette.
~ In a cabinet where you see a water filter cartridge...probably below that cartridge.
~ Look at where your fresh tank fill is. If you have a gravity fill tank (just an open pipe in the side of the camper with a plastic cap on it), the pump will be near there. If you have a diverter valve that sends city water to your coach or to your fresh tank, that complicates things because pressurized water via PEX can go anywhere.
~ In cabinet(s) near the kitchen sink or bathroom - look for a concealing panel in the cabinet that is "hiding something".
~ In my high-wall popup, the pump was right behind the converter/breaker panel. Didn't make sense to me either, because water and electricity don't play well together, but there it was.
Is your pump toast? Probably. It's one thing to run one dry for a few minutes. It's another to run it dry for an hour. BUT, before you give up on it, find the pump, remove the strainer cap, and try to prime it with something like a turkey baster full of water to dribble water into the open screen housing. You might get lucky if it starts to pump that priming water, then it may have enough suction to draw from the fresh tank. Then again, if you can't hear the pump running at all, the motor may be dead.
One more concern, a pump that has been run dry may also have a damaged check valve. Even if you get the pump running, it may not hold pressure, and it may run every couple minutes to restore pressure lost thru the check valve. The good news is that pumps are cheap and easy to replace. This was my experience that led to locating the pump in my PUP (pop-up).
I urge you to add more detail about your rig's identity. I googled 2013 RS320, and got all manner of things, from a fiver to tractor equipment to end-of-life supplies to a Yamaha electric guitar. I assume you have a fiver, but there were several rigs with that model number. I suggest you edit your signature to include the brand ("Columbus"??), full model, type (fiver?), year, and any other clearly identifying details. That's why I don't know what type of fresh tank fill you have.