Are these chips the ones they were selling in the gift shop when they 1st opened? If so gaming made them pull them. The reason was they were 39MM, same size as value chips. No No for gift shop sales. Must be different size than a gaming chip.
If this is the case, then 18,000 were never sold. Could be the answer. I must admit that I never heard of the HR brass cores until this thread. I do know chips were ordered from the gift shop for the above reason, right after they opened.