I believe you that it doesn't work in A2, but I only built the mission in A3 - after one of the game mode updates. The one where the AI could request transport after the helicopters DLC.
I was flying the mission with no errors and with everything working in the scripts, otherwise I wouldn't have come to report it.
When I'm back at a computer with some time I'll see if I can find the note that you can setVar/getVar on tasks, but ultimately its broken now/still and should be fixed.