While I have my doubts, a couple things should be pointed out. That "ask.com" link is silly - anyone can post anything, and there is nothing authoritative behind it. But if you do a search for "Coca-Cola" and "green," all the answers deny that Coke was originally green when it was introduced and was later changed to brown. None of the answers address whether the current manufacturing process would give us a green liquid were the caramel coloring withheld.

Until then, I cannot yet say that this myth is busted.