Craig,
While I haven't seen or played Green Brook, I have played quite a number of Robert White courses and would be very surprised if that's his bunkering. While he could get a little flashy at times, it almost seemed superfluous and not purposefully so.
My strong hunch is McCarthy, as you surmise. At Hershey CC West there are not only oodles of bunkers, but also much in the way of bunker clustering and bunker "patterns". I also suspect some more have been lost with time.
As far as when they were removed, and by whom, it's likely that they fell victim to maintenance cost-saving measures during the depression (or possibly Tillinghast came through during his 1930s bunker removal period
), but the book, "Golf Clubs of the MGA" cites RTJ Sr. coming through in 1948, who "rebuilt a few greens and tees", and Hal Purdy who created a new par three in the 70s.