AMC operates what 900 helicopters under various names and certificates? I suspect this infraction in Jacksonville is A) Just one FAA inspectors flexing his mighty pen. B) just the local FSDO flexing its mighty pen.
I would also guess that AMC isn't so strapped for cash it can't replace a few corroded parts. There is always some pilot, mechanic that has a friend at the FSDO and asks a favor.
Also, one person may call a single pit marked 'corrosion beyond service' another may say it's fine.