~Edited out gibberish.~
Try EscapeAreaMove instead of MoveBetweenAreas, though I'm clueless why that wouldn't work. I know EscapeAreaMove will work since I used it in Hessa. It's just the escape part is kind of silly when the NPC isn't even visible.
Thought about it some more and realized why it doesn't work. It has to be used in conjunction with ActionOverride, so we can specify the object to move. I.e., your NPC doesn't move because this is in an area script, not a script assigned to the NPC. Without ActionOverride, it's like saying "Move X Here." ActionOverride lets you define X.
So instead of MoveBetweenAreas("AR0305",[758.799],13), use ActionOverride("F1GARTK", MoveBetweenAreas("AR0305",[758.799],13))
I will edit my original code.