Have you tightened the fuse box bolts to the proper torque yet?
I had this happen to me one time at 1250 miles. Checked the bolts and they were far from what they were specified to be torqued to in the service bulletin. I find it hard to believe that GM has not been able to correct this issue on the assembly line in 2-3 years. Something this simple that causes such a big impact you would think they would take care of. Im not saying this is the root cause of the crank and no start but I have not had the issue again in the last 1000 miles. It is worth trying.
Not sure if it is related or not but before I torqued the bolts, I noticed the voltage gauge on the dash showing 12ish a lot while driving. Since torquing, I’ve never seen it down there again. It’s always 14 or slightly above.
2021 3.0 Silverado