First of all Diazanon is one of the most over used organophosphates in the landscape enviornment. This means that you have a much higher risk of the target pest having immunity to the chemical. I would try to go with a newer, and safer, class of insecticide. Merit is labled for Mole Crickets and since timing is critical, it is unlikely you will kill mature mole crickets with any chemical, Merit will give you a very large window.
If you want to verify that it is mole crickets, mix 2Tbs lemon sented dish detergent in 2 gal of water and apply to a area of turf 1 square yard. The soil should be damp when doing this. You will see the immiture crickets poping up to the surface.
The harder I work
the luckier I get.