Does "all fuses" include both fuse boxes and the maxi fuse at the battery?
]Did you check for voltage at the fuses?
And really crank down on the 4 bolts! Best to loosen them then retighten until you pass "fear of stripping".
Don't worry about bad computers, unless somebody did something stupid that caused arcing or burned wires. You said everything was good when parked and as if by magic dead in the morning.

Again, was the battery replaced before or after the problems? How long before or after?
Again, what about recalls?

 

How about relays 34 and 51 in the underhood fuse block?

And yes, what your vehicle's status with regard to recalls? Both donbrew and I have links in our signatures so you can check. If You Can't see our signatures, you are on the mobile site. They're only visible on the full site.

 

He said he changed the battery after all of this started happening. I ran his VIN and there are no open recalls. I loosened the 4 screws all the way and then cranked on them. And yes, All fuses means ALL fuses. And I did check voltage at the fuses even after I checked with my test light and all good.

 

That leaves the nut under the red boot on the battery box to tighten, and the battery cables to inspect for cracks in the connections , check that fuse out back by the battery also.

 

Did he feed it after midnight?
Did you push all of the fuses to make sure they are all seated? The have a habit of popping up.
When you tightened the 4 bolts did you go past "afraid to strip"? Especially the one in the rear, near the start and run relays.
Check the ECM connectors for loose pins.