Welcome to our little corner of all things RV.
I've got no answers about putting an A-Class Outlaw in fhe freezer: I've got a C-Class...
But I can tell you that the issue of keeping things unfrozen, is the name of the game.
The "Outlaw As" have heated compartments for the tanks... they may still be running plumbing through areas that will need extra protection. You may also want to add some heaters (or at least some 100 watt lightbulbs...) down by the tanks, to help keep the contents in a fluid state.
I think that it's a bit of a case of give it a try: see what needs changing, and try it again.
(What kind of sleds do you have?)