I coated my 22 Camaro ZL1 last summer and it is a constant dust magnet. I use Echo2 diluted as a quick detailer since I never drive in rain so it never gets dirty but just very dusty. I use a car duster followed with the Echo2 detail solution. I am guessing it is the Echo detail spray causing the static cling that attracts the dust and pollen.
I doubt the Echo2 is causing that static. On the flip side, I could see the cloth fabric strands of the duster causing static as it rubs along the body panels. Recall what happens to someone's hair sometimes when they rub their hand along a sweater or blanket. Also, it just might be the vehicle. Some cars just seem to have issues with static, others do not even when you clean them the same.
There is a very easy way to test if the Echo2 or the duster are causing the static. The next few washes of the Camaro, leave the Echo and duster to the side and just wash it the same way you wash your GMC Sierra. After those few washes, if the car still is a static dust magnet, it would be the Camaro not the Echo or the duster. If the Camaro is not a static dust magnet, than you have isolated the issue to either the Echo2 or the duster. So, make the next few washes, rinseless washes with Echo2 and do not use the duster, and dry with a towel just like you use to dry your Sierra since it seems that towel does not cause static. If the static and dust return, it was Echo2 which I doubt will be the cause. If the static and dust do not return, it would be the duster causing the issue.
On a side note, I would look closely at the Camaro in the sun light to make sure you are not swirling the paint with the duster. I have probably seen at least a dozen show cars/garage queens which at one time were compounded/polished swirl free only to see swirls that perfectly match the arm stroke of the owner using a car duster at a car show. Dust being drug along clear coat with a car duster can and often does still swirl paint. Doing a good rinse free wash does not take much longer than a dusting and quick detail wipe down and is infinitely safer to the paint.
Is there any way to stop the dust on my camaro? Is there a detail spray that will not attract the dust?
I don't know of any detail sprays/rinseless washes/waterless washes/spray waxes/spray sealants which actually attract dust, I can't imagine they would survive on the market once it was discovered that it attracted dust and as long as Echo2 has been on the market, I feel pretty good that the Echo2 is not the cause. There are however, detail sprays which advertise as having ingredients which make them static resistant. So, if you do the test above and discover it is the car itself, you could do some research online and see if you can find a highly recommended detail spray for static resistance.