I'm not sure this had to be the result of a grounding.. it seems pretty clear the boat was at some point transported sans keel and that the keel was attached afterwards (by an "unknown yard").
If it had been inadequately torqued, then faired, and then sailed some distance these cracks in the fairing would be expected, as would the apparent 'gap'.
In any case it's not something one would expect to find with a NEW $300K boat, that's for sure. The dealer should make it right... properly.
1984 Fast/Nicholson 345 "FastForward"
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)