That is a difficult question to answer.
Do you believe you have water in the keel again, after you did the repairs?
In a normal condition there should not be any water in the keel.
If you think there is water then you want to drill a hole in the lowest point of the keel. Water will drain down.
Then this winter you want to inspect the keel and close all possible places where you think water if entering the keel. I would even go so far as to try and attach a vacuum pump to the bottom hole in the keel to suck water, as much water out as possible. This may take time.
Once closed up and water removed, then sealing the hole in the bottom should prevent any further damage. That is unless you take the boat out next year and use the keel to search for submerged rocks.