Side/window Air Bag problems of the 2009 Honda Odyssey

We were driving down a residential street, on easter morning on our way to church, at 20-30 mph when our passenger curtain-side airbag deployed. There was no impact. We did not hit anything and no one hit us. Our family (two adults, 5 y. O, 3 y. O, and 6 week old) were in the car with no injuries. We took our case to the local Honda dealer, where they ran diagnostics. They found no issues and referred our case to american Honda (case #05962968). Their engineers and specialists did not find anything wrong either and will be denying our claim (letter of rejection pending). Our state farm insurance will not be covering the issue either (letter of rejection pending) (case#43-1404-3h2). I believe there to be an issue with the airbags since only one major airbag deployed and not the entire airbag system. No airbags deployed from our dashboard. I feel that Honda should be covering our repairs because no impact occurred and this is a major safety issue. Our insurance company has pictures and all documentation including a crash report on the vehicle. I currently do not have them, but can retrieve them if necessary. Thank you for your time and consideration.