I wasn't sure at the time that the outside faucet was the same supply as the kitchen, or if it was irrigation water. But logically, it must be since it is still turned on.
And yes, I do have an air compressor with a pressure regulator. However, if I remember, the connection of the compressor at the trailer itself had a little leaking going on. I can probably get that plugged tightened up and try out the air before the water. I'm sure I winterized just fine, but it would be peace of mind before the trip...