It appears from the pictures that the dull "rollers" are smaller diameter than the shiny ones. This is quite evident when you look at the gaps between adjacent shiny rollers and adjacent dull rollers.
I suspect that quite a number of the rollers have actually cracked and split off and the dull ones are actually the inner sleeve that the pin slides through and the rollers fit over when the chain is assembled. You can verify this by measuring diameter of the rollers. If you look at the end link in the bottom picture you can see that the "roller" is actually the inner sleeve that projects all the way through the side link with the same diameter.
This is a very unusual mode of failure for a D.I.D. chain since it would seem to indicate brittle rollers that could fail by cracking under heavy impacts from a worn sprocket. I would expect poor heat treatment from a cheap chain, but not from a good brand name like D.I.D.
There is evidence of rust around some of the O rings suggesting the pins are dry and rusty inside. How old was this chain? Was it maintained at all in 4500 miles?
This is a good argument for replacing chain and sprockets together.
2004 Rebel 250, 2003 BMW K1200GT (roadburner), 2004 BMW R1200GS(all purpose),
1973 Norton Interstate (in a box in the basement)
1968 Triumph Bonneville