Can’t see the point of filling the hole with epoxy.
If you’ve removed all the loose parts and magnets still seem to be held in place I’d leave it as is and start thinking about getting a new motor/can.
With a hit like that you might run into future motor failure with magnets coming loose. It’ll be interesting to see how the battle hardening will affect any possible weakening though. If you keep running with this, keep us updated on how it holds up.
I’m going to fill with epoxy mainly because I’m not 100% sure I got all little chunks out.
And maybe to keep more chunks from coming loose.
Plus it is really not much trouble since I already have it all apart…