At 25:39 as a phone conversation ends, Winston nods to acknowledge what the IA officer said. The person at the other end of a phone conversation cannot hear you when you nod.
At 11:51 while Allyson and Chance are in the police car, the driver identifies them on the radio as "3 William 56", this is the same call sign used by Murtaugh and Riggs in Lethal Weapon, and the cop in the passenger seat is named "Gibson".