I disagree with your…
I disagree with your Sherlock Holmesing, looking at which direction the tire would have come off and out from under the vehicle it's very easy to see how the cladding could have been knocked off by the wheel exiting the wheel well at a high speed. My John Holmesing tells me that this rim very well could have cracked under a stress fracture. Meaning that any bump in the road could have reacted on a stress fracture and caused an overall failure. It is after all an aluminum alloy rim.