I have a different type basket, but I'd like to try this method. Can you offer up some details?
They thawed in the refrigerator. Put them in a bowl with olive oil and mixed around. Sprinkled with 1 1/2 tsp each of kosher salt, black pepper, garlic powder, and onion powder. Cover and put back in the refrigerator for a couple of hours. Got the grill heated up to around 400° and placed basket in. Cooked for about an hour. Then heated up a 50/50 mix of butter and Franks hot sauce to pour over them at completion. We couldn't stop eating them. No leftovers and nothing for the dog! LOL
On a side note I have 2 other baskets that I used on the Thermador. They held the food tight. This basket actually has "wings" staggered inside to help with the tumble action. Not sure if that comes into play. It definitely has a higher capacity.
I also only used the rear infrared burner to cook.
Good luck and let me know how you make out!