Even when our dead bolt broke inside we were still able to manually open and close the dead bolt. From other posts that seems to be the common failure mode.
You can drive without the deadbolt being locked, we've done it before. The Argosies didn't come with deadbolts and who knows how many thousands of miles have been racked up on those vehicles!
Air forums # 1674
1974 20' Argosy Motor Home
1974 31' Excella trailer (parting out, as of 4/1/2015 I have wheels, brake drums, windows & holding tanks left to sell)