What ground wire shouldi be looking for

What is your question?

So i had a company come to reflash my ecm. They said everything was fine ECM and PCM are good and there's no reason the truck shouldn't be running they said their data showed the none of the cylinders were firing ( i have alreaedy changed spark plugs abd boots)they ran a test on a spark plug boots and they said it was Orange spark instead of the blue Spark they said they think they may be a ground wire is broken causing an open circuit where should I begin to look I have a 2003 Dodge Ram 1500 5.7 L Hemi they relearned the throttle to the ecm also