Sounds like a totally legit story. How small was the "bump" really? How can you judge how far the truck went off the ground from inside? If you just "went over a small bump" it shouldn't have come off the ground at all.
People have wheeled B2s for decades. Granted, most swap to manual hubs (which were available from the factory), but even then, a "small bump blew apart" the auto hubs? Please.
The '91 Explorer Sport's D35 front carrier, 4.0, and M5OD manual (if equipped) were better, but all swap right into a B2, and nothing the B2 had was particularly bad except for the A4LD automatic, which the Explorer had too. And even then, well maintained A4LDs often did 200K+ miles. Most people just didn't maintain them.
The B2 would have been better with '91-'94 Explorer running gear, but they will walk all over a '95+ Explorer off road out of the box. Not to mention everything short of the Wrangler today. A new 4Runner might hang, maybe, if you can stomach thousands in body damage.