Failed Rocker Arm

Is the failed rocker darker bluer than the rest is is that a photo effect?

Could the push rod be plugged causing oil starvation on the pivot, creating heat, causing metal damage?

All that being said ... The broken rocker looks like metal fatigue, grainy, vs. sheared.

That being said.... Would a broken rocker produce smoke from the tail pipe even as it was in the process of failing? (based on symptoms I assume it didn't happen all at once but began to let go little by little till total failure)