The auditor clearly understood the RAID configuration. You can watch him describe it in the video of his testimony.In his testimony he clearly and unambiguously states that he didn't know it was RAID 10 and so he had to run scans to determine the configuration.
It was in the process of running these scans that he identified the MFT in question.
You just confirmed that the auditor wasn't confused about the RAID configuration. As he testified, the county did not tell them what it was so he had to figure it out. Which he did.
Don't fall for CNN disinformation.