I move boxes in my home frequently, perhaps as often as once a week.
Mar a Lago is a large residence with an employee staff. No doubt the staff is moving boxes, furniture, and other items frequently. There is no crime in moving boxes. If the movers didn’t know what was in the boxes there is no evidence they were moving government records. No issue.
I think you are missing the point.
Trump pointed to this secure room and said, ( in essence) “This is the secure room where they have been kept.”
If this guy’s story is true, Trump misled the Federal Agents. Intentionally.
Like Nixon…Trump is going to get screwed by a custodian.