I wouldn't trust Huobi to report real volumes. I don't mean anything bad for ETN, that's just me not trusting any of the exchanges that report hundreds of millions, some even billions of $ in trading every day during a silent flat market.
I don't have any bases for this, but it's a fact that they can fake volumes by trading between themselves.
So if they can do it, then I believe they also want to do it.

Look at the trading between Huobi Token and BTC, it's the exact same figure. It's like 98% of the BTC traded is to buy/sell Huobi Tokens!
(link: https://www.coingecko.com/en/exchanges/huobi)

I'm happy with KuCoin, Kraken and Bittrex, so no reason to go to a Chinese exchange with fake volumes. Thankfully ETN is traded in at least one of my 3 favourites (KuCoin) so all's good!