Not speaking to the authenticity of the photo, but if cinder blocks aren't filled with concrete they aren't exactly super puncture resistant. They actually aren't all that hard to punch through.
I doubt it's very easy to move the barrel externally so I'm surprised the wall is there at all. It's probably even supporting part of the tank's weight somehow.
Honestly best place it could have hit. Didn't damage the door or even the control conduit. If they don't do more damage backing up it won't be a complete disaster.