Holy shitballs man. Glad you guys were able to have that thought about the wheel/tire bouncing down the road.
This is in now way a jab at you for running spacers, but this is exactly why I will not run spacers, on any vehicle. Yes, there are great companies out there that build them, Spider something pops in my head as the first choice. But it still adds a second point of failure where one didnt previously exist, and these trucks are too heavy for me to trust spacers on. I'm sure a good number of people will disagree with me, but spacers to me are a situation like this just waiting to happen. There's no reason at all if you use aftermarket wheels to not buy a set with the proper backspacing/offset from the get-go.
That said, seriously glad you're ok. Again, this is not a jab at you in any way, just voicing my opinion about spacers.