I have the same trailer as yours.
You can get to the back storage locker by removing the drivers side bed. Once you have the bed base up, you can access the storage from above and using pliers, remove the nut holding the lock - it will come out to the front.
Take it to a locksmith and he will make a key for it. Hopefully, all the other door locks will match this key - mine did. Also take your broken key to the locksmith, and they can make a new door key for you. Get three!
If they are not keyed alike, you can get to the refrigerator door from underneath - harder than the back, but doable. The only bad one would be the battery box behind the front door. Good Luck.
P.S., I bought a lockable key box at Home Depot. Put extra door key in it and mounted it on my front frame.