Look at this way to cause issues the water has to freeze hard!
Do you make ice cubes in your RV freezer? Just how long does it take to make ice from water that is likely 50 degrees when it goes into the trays???
Our freezer registers -10 most of the time, water still takes a several hours to freeze. so if your trailer gets up to say 60 inside during the day, do you think it gets below freezing in the trailer over night at 25? You should be good for a couple of nights IF daytime gets back to the mid 50's or 60's, and the temp doesn't drop like a stone at night.