Since your scripts have the following line:
Did you send a signal in your map for the AI to commence their attacks? Your map need to have the AI - Send Command (or something like that, check GUI triggers in AI category) for the attack to commence.
I did. When Arthas steps in the force field region. Thats the signal. Also i put the send commande triggers.
AI Command
Events
Unit - A unit enters ForceWallDiscovered <gen>
Conditions
(Entering unit) Equal to Arthas
(Clicked dialog button) Equal to DialogButtonArray[0]
GameOver Equal to False
Actions
AI - Send Player 17 (Wheat) the AI Command (0, 0)
AI - Send Player 12 (Brown) the AI Command (0, 0)
AI - Send Player 7 (Green) the AI Command (0, 0)
AI - Send Player 6 (Orange) the AI Command (0, 0)
AI - Send Player 7 (Green) the AI Command (0, 0)
AI Command 02
Events
Unit - A unit enters CityEntrance <gen>
Conditions
(Entering unit) Equal to Arthas
(Clicked dialog button) Equal to DialogButtonArray[0]
GameOver Equal to False
Actions
AI - Send Player 1 (Red) the AI Command (0, 0)
AI - Send Player 2 (Blue) the AI Command (0, 0)
AI - Send Player 16 (Violet) the AI Command (0, 0)
AI - Send Player 21 (Coal) the AI Command (0, 0)
AI - Send Player 11 (Dark Green) the AI Command (0, 0)
AI - Send Player 3 (Teal) the AI Command (0, 0)
AI - Send Player 9 (Gray) the AI Command (0, 0)