Exact same thing happened to us. The locks are stiff and the keys are junk. They should have given you two sets of keys.
A. Stick the "half" key into the lock anyway, try to turn it to unlock.
B. Call the dealer, get the second set...DO IT!!
C. If one of the other compartments is unlocked, take off the lock - just a few screws, take it to a locksmith. Get a new key, only a couple of dollars.
D. Is any part of the key sticking out? Use needle nose pliers to pull it out.
Luckily when ours broke I was able to stick the remaining part of the key in and twist it to the unlocked position. I took off the lock, got out the key, went to a local locksmith had 5 durable keys made, done.
2015 Georgetown Forest River 351DS MH
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2006 Jay Flight 29BHS TT