I heard an interview with LBJ’s long time mistress in the 80’s. She said Lyndon met with several men in suits in their Dallas hotel. After they left he said Bobby K wouldn’t be a problem any more. The next day he was assassinated. She said he had had people killed, but it “was just business” and that he was a good man. This was on a Lubbock talk station.
There is an interview with her where she talks about this on YouTube
Her story is debunked. She made stuff up. Not a rare thing in this realm.