There are some credibility issues with the OP.
The OP started another thread under a different user name, but then posted under this user name later in that thread. The OP stated in the other thread that he/she was not speaking with the agent (for various reasons), but then states he/she was told by the agent about the disclosure issue.
Here is the thread:
https://www.city-data.com/forum/real-...l#post44830038
With that said, OP knew of a leak and did not disclose that to the buyer. That is a problem.