i'm asking that myself.
Those are FM bearings. And i bet those shiney spots is due to fitting and rotating the crank with very minimal lube on them. .
I also think there is something to said about that one rod bearing being killed but the other bearing are intact and not down in the copper.
The # 4 main bearing is showing some abnormal wear marks on it aswell. how much taper is in those main caps.
Now pertaining the thrust bearing when assembling the engine how was the thrust bearing set? Was the #2 cap fitted along with the bearing to see how they matched up top to bottom. One thing you gotta watch on the FM bearing is bearing thickness is not held to a very tight tolorances.
These are just some questions/comments i have about this issue. I'm not here to try and blame anyone or anything.