Re: That can't be good..... right?
I'm not familiar with the innards of your boat, but many boats with an encapsulated keel also have a "false keel" - this is a void typically behind the lead. Clearly it needs to be filled with something, but filling it with solid epoxy is expensive, so boatyards have been known to fill it with all sorts of low-density high-volume fillers.
Personally I would see if the water continues to drain out. If not, drill an oversize hole, fill with thickened epoxy; then re-drill to the correct size, and don't worry about it.
If water continues to leak out, you may need to remove some of the glass around the hole to expose the saturated area. This happened with me; the fiberglass "skin" had actually "rotted", and a 3'x3' area had to be removed to expose the core and allow it to dry out, then refill and refinish. If you are on the hard, this is not so intimidating as it appears, as fiberglass is a lot easier in many ways to work with than wood, in that the new epoxy chemically bonds to the old, leaving the repair as strong as the original (I hope).
It'll be interesting to see what others think....