Hola,
few months ago i was shooting stuff with my z1 and my colleague was shooting with a Z7. We white balanced on the same piece of white but what i had on my lcd was pretty yellow compared to the lcd of the z7...
How come?

Second thing: the zx7 is long way light better cam!!!!

I had a shoot with two Z7's and they didn't exactly match as indicated by around 100 degrees difference in the color temp indicators. You may already know that best results are obtained with the cameras side by side.

they were side by side but, the monitor colors were from 2 different worlds...

One other thing I thought of was camera profile. Were both cams set to the default profile?

I'm not sure the color difference matters unless it was noted on the same monitor