How do you correct this???

[Smoothieking]

I had something similar last night. I was L after a made basket by A. B inbounds under the basket (can run baseline). A deflects the ball OOB on the sideline. My partner tells B inbounder that he can run the sideline!?! (I find this out after the fact) After B inbounder takes several steps OOB, I call travel. My partner conferences with me and tells me that he told the inbounder that he cold move! Unbelieveable!