Is it possible that one of the dock cables came loose?
Yes, that is very possible. The relevant FAQ entry is
here.
I would also see if the installers connected a power line directly to your battery, and if perhaps that's what's come undone. Or perhaps some other wire connection running between the empeg and the electricity, such as a fuse link coming undone.
It's also possible that if the installers did a poor job with the wiring, the bump caused a bare power connection to touch frame metal, thus blowing an inline fuse. Check all fuses between the empeg and the electricity, including the inline fuse on the yellow power wire.