You are in Michigan. I know the temperatures there are colder than Indiana and we've been in the upper 20's low 30's for a few days now.
I imagine you camper has not been heated, and it's cold inside. If that is the case, then the inside of your refrigerator is probably somewhere around the same temperature as it is outside, maybe slightly warmer. So if the outside temperature is.... say 25 degrees, the inside of the camper is probably 35 degrees and the inside of your refrigerator is probably 35 degrees.
The refrigerator won't fire on because it thinks it's already cold. Warm the camper up, get the temperature around the refrigerator warmed up, or better, open the door of the refrigerator and heat the inside of your camper. Once the inside temperature of the refrigerator warms up, above the "turn on spot", it will then fire up.
You might be able to take a hair dryer and simply blow it inside the refrigerator to warm up the temperature sensor. I bet it will fire up then. Once it fires up, it will continue running. You'll need to keep the inside of the camper warmer too.