Yes you should add a warning. Because BTG website https://bitcoingold.org/ removed the link but it is still circulating from old forums posts and its linked on Google and people are still falling for this scam and not only losing their BTC but they are losing every single coin they own if they import a seed like an Exodus wallet because that wallet houses many different coins.

In my opinion people shouldn't withdraw until more exchanges support the coin. So far the only large exchange is Bittrex. I am waiting also for Poloniex and Bitfinex to enable deposits of this coin.