So this is something I would suggest to skip: When one enemy sees you, all would know of your position (100%). You would either need to shoot him (in this case the enemy would be blind again) or move out of his sight.

Giving the enemy a certain % of what to do next is problematic too: it is difficult to define a suitable behaviour in each situation for the AI at all. Saying that in between 35% to 75% of all cases he wouldn't do even that, do something else or nothing at all means that besides the JA2 enemies already already are dumb AI, they are even coded to behave extra stupied/wrong.

If soldier.orders->Guard OR soldier.orders->Stationary
then chance = 50
else chance = 25
If soldier.attitude.defensive chance = chance + 15
If random(100) < chance
then radio
else investigate