I don't have the answer, but what if the kernel of your idea "cracks the code" of the triple honk? At least for people with Aux switches, you'll be renowned the world over, discussed over camp fires, "yeah, thanks for noticing, I used the Goofy Solution" Ya never know.I'm sure it can be done, but could one of the Aux Upfitter switches be used as a toggle to switch between running the factory horns on the factory switch and Air horns on the factory switch? Like say I have Aux 6 setup so when it's on I'm running the air horns, but say I don't want the triple honk to scare the crap out of people in a parking lot when i leave my truck running for my dog I can turn it off and it'll use the factory horn.
For now...for the dogs...I guess the fob against the rear window thing works.