Is there a list of exchange wallets?
I don't know...
Tether always was a scammy shit, take a look in https://tether.to/legal/
Quote
Once you have Tethers, you can trade them, keep them, or use them to pay persons that will accept your Tethers. However, Tethers are not money and are not monetary instruments. They are also not stored value or currency. There is no contractual right or other right or legal claim against us to redeem or exchange your Tethers for money. We do not guarantee any right of redemption or exchange of Tethers by us for money. There is no guarantee against losses when you buy, trade, sell, or redeem Tethers.
EDIT. For now site is dead.
EDIT#2. Nice article --> http://www.trustnodes.com/2017/11/17/tether-bitfinex-new-mt-gox