Short of finding a vulnerability in Renzo, the trader's only real choice is to plead with Renzo to change their smart contract in such a way as to release the funds. While this is technically possible, Renzo has told the trader they could not grant his request due to "regulatory limitations".
Trader reveals he lost $28 million to bad copy-paste
After apparently exhausting all his other options, a trader has put out a call to "all skilled hackers and white hats out there" to help him recover 7,912 Renzo staked ETH (ezETH) he inadvertently sent to an inaccessible address back in June. The tokens were priced at a little over $28 million at the time, and are currently priced at a little less than $26 million. According to the trader, he copied the wrong address to his clipboard before making the trade, which rendered his funds permanently inaccessible.