The team also placed a call to Palmer's representatives last week, before cutting the quarterback's brother, Jordan, a backup passer.
ESPN first reported that Palmer and Brown huddled at Paul Brown Stadium the week of July 25, sometime after the NFL lockout ended and before the Bengals reported to Georgetown College on July 29 for training camp.
It's unclear whether the meeting happened before or after Brown's harshest words for the quarterback July 26.
"Carson signed a contract, he made a commitment," Brown said. "He gave us his word. We relied on his word and his commitment. We expected him to perform here. If he is going to walk away from his commitment, we aren't going to reward him for doing it."
The Enquirer reported that while the stalemate between the sides is ongoing, some within the organization believe that Palmer, scheduled to make $11.5 million this season, could end up reporting to the team at some stage.
If that ever happened, offensive coordinator Jay Gruden believes it would take time for Palmer to learn his new offense.
"In order to play quarterback at this level in the new system, I would think he would want to practice, and obviously he's made a decision very clear that he's not coming back," Gruden said. "But if he did walk in, I'd welcome him back, I'd suppose. He'd have to win the job."