After looking at the contents of the mission and your .rpt, it doesn't actually look like anything is wrong.
Vehicles and helicopters seem to have a random spawn time, the max is 46000 seconds, or 12 hours (there are two sleep commands, one at the start of the script of 26000 seconds, and one at the end of the script of 20000 seconds). It also appears it only spawns one vehicle/helicopter.
You must have gotten an unlucky number roll and ended up with a significantly large number (4 or more hours). I don't know why the mission creator has set it to max of 12 hours (that's ridiculous!), but he has.
You'll need to restart the mission and hope for better luck, or just keep playing and wait for the eventual spawn of one.
Sorry I cannot help more. I didn't create the mission, so I can't change anything for you without permission.
DaiZy Single-player Developer (AI Units)