Going back to the beginning, and what we do know...............
On the day that Casey was arrested, July 16th, she mad a phone call home from jail. On that call she was very angry, first with Cindy, then with Lee and finally with Christine. She demanded Tony's phone number. Getting Tony's phone number was the most important thing. Casey knew Lee was at the house because she had been watching television at the jail and saw Lee's girlfriend's car parked in front of the Anthony house. If Lee had Tony's phone number, I think we can conclude that Lee is somehow connected to Tony too.
Secondly, there's the police affidavit that was released shortly after Casey's arrest. In that affidavit, Tony had already been interviewed by LE and according to that report had called Amy and urged her to call LE too.
Yes, I know.......my reply was about how LP has started bringing Tony's name up......."Casey messed up, fell in love with the wrong person...... & tonite by name".