Yoop:
A pic is worth 1000s of words. What you refered to as a 'box' is a troff, with feeders (or service), not what I thought was a 'device box'.

From the pic...yes, it is in concrete....but, NOT inside the wall; that may be why you bought a red sticker.

Personally, from what I see in the pic...I would not have any issue.

What Article did the AHJ write the violation on??

John