your floor boards and take a look around the hull
at the leading and trailing edge of the keel
area. In a straight ahead impact as you describe the hull
at the forward end of the keel is put into tension and the area at the aft end is put in compression
stresses normally show more visible damage than tension. Look for fractures, even very fine hairline fractures emanating from the area in something like a starburst pattern. If you see anything at all chances are that there is more damage that you cannot see.
Dry your bilge
and with masking tape wrap each keel bolt with paper towel, get yourself a cup of tea, lie on the floor and watch for a while.
Depending on what you find you may have to bite the bullet. Biting the bullet now is probably a wise thing to do anyway. as your insurance
requires you to mitigate damages and they may make things difficult if you try to put in a claim 3 months from now. I'm involved in a similar case now where the insurance
company is trying to pass on significant damage costs they say were a result of the client not mitigating damages (I'm on their side).