Yes, I did read your post. Bittrex sent me this a few days ago, showing the bitcoin address (receiving address for my Electrum BTC wallet) that I sent it to, is actually a valid litecoin address: http://ltc.blockr.io/address/info/3Mjr6FjR5T5Mc5rSRvKDhPxEYPfmmVzTXR
I was able to export the private key for that address, but can't figure out how to import it into any litecoin wallets, as the private key for this address doesn't seem to be recognized by any litecoin wallets, and won't let me move to the next step (any buttons are greyed out, etc.).
Bittrex escalated this and here's the reply I just received: Unfortunately, I have no clue how to help. It looks like you sent litecoin to a multisig BTC address which is valid on both networks. I don't know the process to recover the funds. You might try posting on the forums.