Yes, you should eventually get it fixed.
Yes, as I have said before, make sure the next time you haul it out, check it out for cracks, or water, and seal it.You do not have to totally drop the keel. When you haul it out next time, ask them to watch for drips spots after they pressure wash the hull. That will indicate where it needs to be sealed. A good boat yard is experienced at doing that. They will cut away enough space around the crack for the new adhesive epoxy to stick. I would not suggest you do it yourself. Keel is not something you want to fiddle with yourself.Since it has already been leaking for over a year, it probably won't do that much more damage for another season. Just tightening the bolts should get you through the summer. Talk to your boatyard. If they are good, they will give you the right advice. This is no biggie, happens often to many boats, and can be easily taken care of.Happy boating.