CAT C15

What’s wrong with this picture? Cat E model.

 

looks like some serious recession there?

as for OP. spun cam bearing will have sent debris through the valve train/camshaft oil galleries.

ideally you'd want to full strip down and clean. how ever just replacing the head and cleaning out all the rocker arm and shaft oil galleries, stripping down the jake housings and cleaning them will likely suffice.

I would also be dropping a main cap and big end off to inspect the bearing condition. also to wash the sump properly. strip and inspect the oil pump too. the head is the last place to get oil. so really the debris will only have gone into the galleries in the head and valve train. anything that ended up in the sump would have got there through the drain ports. where the only other pre filter component it touches is the oil pump.

the bottom end, compressor and front gear train are all delivered post filter oil before the head.

I would be confident in replacing head and cam. remove and wash sump, strip and inspect oil pump, drop a big end and main off to look and sending it on its merry way with a new filter.