Could have been an illegal and the construction company is about to be liable and made to pay a huge fine to worker's compensation I figure.
No doubt. Unsafe practices; probably an illegal worker; probably no safety training for operating the nailer.
By the by I would NOT want to own a home anywhere, let alone huricane country, where 2X4's are nailed to concrete with a 2 1/2 inch nail; that is only 1" penetration, and not even the right type of fastener. 8" X 1/2" diameter concrete-embedded J-bolts, on max 4' centers, anyone?
We have new homes here with roofs caving in, hell, even a few new HOMES collapsing due to slipshod construction here in SoCal !!