Solid cam damage diagnosis help

One of my local customers put a 455 Pontiac together a couple years ago.

Start up/break in went well.
Gets everything dialed in, all seems good.
He’s driving the car on his way to delivering it to the owner...... hears something he didn’t like at a stop light.
Oil pressure looks a tad low.
Shuts it off..... starts it up again..... hears the noise again.

Has one of his guys come get him with the trailer.
Pulls oil filter..... there’s metal in it.

Motor comes out and apart.
Rod bearing is failing.

Happens to give the cam a close look over......one of the lobes appears to be starting to go.

Brings it over to me for a look.
Yup, that lobe is going, and several others don’t look great.
And the wear pattern is right down the middle of the lobes.
I checked the taper in the lathe.
The most taper any of the lobes had was about .0005(1/2 a thou).
The one with the failed lobe basically had none.

Here is the argument against the white box special cams.
They are almost always ground on big production machines, using gang masters......... and those machines have 16 grinding wheels, and grind all the lobes simultaneously.
So, this means there are 16 different wheels, that get dressed individually, that can have potentially 16 varying degrees of taper.
On a traditional machine, or a cnc machine...... the one grinding wheel does all the lobes...... so the lobe taper should be consistent for all the lobes(could be consistently good..... or as in the case of the OP...... consistently bad).