Mmmm I think you can bypass that problem maybe..? Basically when you respawn, set a point to that location, and then order all your enemy dudes to attackmove to that point.
I might just be missing the point tho.
Not sure if this is what you want, but the sight radius field is under the units/stats tab all the way at the bottom. I think that there's no acquisition distance seperate from the sight dist. per se. I get the feeling that if the unit can see an enemy, it moves to weapon range and then attacks.. could be wrong though.