Not sure I think it's likely, though - could have just been a user miskeying something.
I don't think there is any money laundering going here. The point of money laundering is to raise as little attention as you can, and that is not happening here. Weird transactions and income makes you just more suspicious.
I do doubt that explanation though, as $23 millions is nothing for Bitfinex and any of their execs could get this amount from personal funds if it was really needed.
You send your huge-fee transaction secretly to your co-conspirator miner. They start trying to include it in their blocks, and eventually get one (call this block X). But now your transaction is not a secret anymore, and so another large miner can decide to keep trying to mine off of block X-1, but including your transaction. If they can outpace your miner (maybe by spinning up extra compute), they will produce a longer chain in which the $23M goes to them instead of your intended recipient.
It seems like a very large mining fee would change the incentives that are supposed to keep miners all working on the same chain.