Mea culpa.
I looked at the actual policy wording and you are right:
"Public/Private Statements. Any public or private statement of interest,qualified or unqualified, in another club’s player to that player’s agent or representative, or to a member of the news media, is a violation of this Anti-Tampering Policy. (Example of a prohibited comment: “He’s an excellent player, and we’d very much like to have him if he were available, but another club holds his rights.”)"
The only "out" might be if Houston gave Williams permission to reach out to other teams since they were not going to resign him.
What a can of worms...