My exported Gcp have a Z value 30m above my projects

Whenever I import gcp they appear 30 m above my project, when I reoptimize the project will align with my Gcp but in the quality report ill be having RMS error of 30 m .
Could it be that the GCP are extracted from Nad83 utm zone 15 but my project is in Wgs84 Utm zone 15?

This is to be expected because Mapper had to move the images 30.33 meters up. The more important table will be your GCP table. What are the RMS errors there?

Thank you for your response, please find below attached file for the GCP RMS
Note that I am getting my GCP from the Lidar data USGS which is accurate to a certain extent ( less than 1m accuracy )

This is as good as it gets. The errors are so low that Mapper rounded them down to 0.000. However, I am slightly concerned because I have never seen an RMS error so low.

What about my Z value Geolocation Error is -30

The absolute geolocation variance is telling you how far the images had to be moved. Since you have GCPs, this is not of importance since the GCPs will dictate the location of the final outputs. Not the location of the images.