Mmmmm I suppose it could have tipped back...

Either way...that'* messed up and looks like some dumba left the boom up...

The tip of the boom was left about 2 feet too high, it hit the lower "skirt". The boom rotated back as it went through and popped out the top of the bridge, but not quick enough for the rest of the machine to sit still. You can see where the whole thing swung up and the cab contacted the bottom side of the bridge. The trailer instantly broke away from the truck. That'* why it'* still underneath the backhoe.

Wow that is impressive. Imagine driving along and seeing that mast poking up and cutting across the road in front of you

Yes, I can see how that occurred as Wikoff has outlined.
I never would have thought it would have caused so much damage and is a testament to the strength of those crane booms....not even bent, visibly.

It buckled near the end.

I'm assuming that wouldn't be covered under Hyundai'* 100,000 mile warranty? That'* crazy

or the weakness of the bridge

Well, it basically was an 8-ton steel 60 mph projectile. They may have had to tear down the bridge and rebuild, but I think it held up pretty respectibly.