I’ve seen damage on bearings just like that from shops that don’t have the proper tools to run through the bores after a bore and hone. I think my shop calls it a broach. It cleans all of the grit that gets stuck in the microscopic groves of the cly wall after a stone hone. I really clean my cly bores with ATF and a clean paper towel till it comes back with no color except red. It looks like grit got in your oil somehow.