it's all about timing.

[bacon]

The bus comes from the other side of depot, right? So what if you unload a couple bullets on a zombie and a stab, buy the depot door and run to the back near the navcard, open bus doors and if you do it fast enough it could be a bridge for us up that ledge? Maybe even a glitch spot atleast..

[HotZin]

The bus jumps from a ramp that was formed from the other side, it doesn't actually travels through a wall.

Also it is simply impossible to get back there in time. By the time you open the door, the bus will already be turning right.

[dylandto]

The only results I got was i turned out to be under the bus and died by lava. It pretty funny because my friend couldn't revive me because I dolphin dived and the bus came over me.