Here's a video of Gravano testifying about OC involvement in boxing. He talks quite a bit about a dispute over a certain boxer between the Gambino family and Bufalino family. At this time it seems he absolutely recognized the Bufalinos as an independent family.
At 8:50 he starts talking about the dispute and mentions "the Bufalino family" by name. He also says Eddie Sciandra was the consigliere for the Bufalino family.
At 27:50 it shows a surveillance video of Gravano, Jojo Corozzo and Eddie Sciandra.
https://youtu.be/aHhuC-T-xlM