Green Beer

Yep, completely agree. It shouldn't matter who they're contracting with for hops, to that much of a degree. You can adjust/fine tune based on acid and oil content and should still get an almost exact, though very slightly different, replica. Case in point, during the citra shortage back around 2010, they stopped producing Hop Drop for a few months because there was literally none on the market to buy. Sierra Nevada (surely using a different hop source) was kind enough to sell them a fairly substantial quantity and they pumped out a few batches that were just as good as the pre hop shortage.
The grain supplier should have a negligible impact, and lastly, they should have a house yeast culture, so that shouldn't change. There's really no viable excuse.