Misfire on #3 that two shops can't figure out

[madtrucker2016]

I remember there was a post I read on this forum, it was the same problem, and this mechanic, I believe, was from Texas, went to the guy's house and fixed the truck in the guy's driveway. The problem was electrical; he really chased that thing down. He used a snap-on meter. The truck was a Big Horn, same year. The oscilloscope he used it showed the wave patterns. I also believe he posted it on YouTube, maybe give it a try, looking it up.

 

[RoadBoss2]

-Do you feel the misfire idle , driving or any specific pattern ?
-Or is just a swift moment enough to trigger the code ?
-A friend has a 6.4 in a 2014 2500 , we got to the point of a P031 and we could feel it . Swap plug with cylinder #3 and coil from Cyl #4 no change . Swap injector , no change , pulled valve cover intake rocker #1 was barely moving.
But we had hard symptom as well , the code , detonation and the flashing check engine light.
Found a 50,000 miles complete engine . So I inherit that 6.4 to fix and fit in my 2011 1500 ...