33rd Dispatch is the dispatch unit for the 33rd Infantry.
Description[]
They are heard for the first time in Chapter 1, when Alpha Patrol is ambushed by Insurgents.
"33rd Dispatch, this is Alpha Patrol. We're under attack. Repeat, the Insurgents have us surrounded. Request immediate assistance. ... Shit! Martzen is down. We need backup."
After that, they are never mentioned by name again, but they can still be heard throughout the game.
Presumably they were killed when Delta Squad breached the gate house in Chapter 14, as they are never heard again.