How did the main get deleted in the first place? Data is volatile, and a simple mistake can wipe out data. The mere fact that my main was deleted after the closure of FFXIV v1.0 is proof. In no way is a backup safe solely for its namesake; it, too, can be lost just as easily. I'm not saying that it's likely; I'm stating that it's possible and that the representative helping me said that he can't say whether or not it's safe.
I didn't make a thread for you to soapbox; I made a thread to resolve an issue and to help others with any similar issues.