Don't think there was such dispute, might've been an excuse used later on though. Chin wanted him dead for the Castellano murder and put that plan back into motion after Gotti was released from prison after winning the Giacalone case, and Manna was heard on wiretap talking about it. Manna was demoted, Chin then saved face after Gotti was alerted by the FBI, and during a Commission meeting in relation to a beef with Anthony Casso & Anthony Ruggiero, Chin lied and said Manna was acting on his own.