I think I had explained this

in a post way back then. I sent a large deposit to poloniex, put the wrong memo (which is like sending no memo) and the money just got to Poloniex and had no path to follow so ...

The money just fell into the poloniex account.

Like when you send a friend some steem and they are in the same room - no need for memo. They know who it's from.

I got all the AI auto answers that could not possibly be related to me forgetting a memo. I thought I was done. But, there may be a chance.

Oh, He thinks it might have been deposited in another user's account (the memo I put was a bittrex memo - doubtful they would align).