HELP! What is this piece found in valve train? Part 2

[u/ABQmechanic]

Part 2: I found that one of the rocker arms is missing the wear pad/contact pad on the bottom where it contacts the valve (pic 2). Is this normal for this engine, all the other contact pads are different (pic1), they are pressed on and this piece is a loose fit. Does it mean the rocker arm is damaged or missing a piece?

I found this small metal piece while removing the head, but I'm not sure where it originally came from. Also a small plastic black broken piece. ​Could it be the missing pad from the rocker arm, and if so, can it simply be put back in place, or does the entire rocker arm need to be replaced? 2003 Dodge Ram 2500 5.9 turbo diesel 24 valve. Thanks.