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Obviously as what others mentioned in here, there is no direct connection between 2fa and your usual crypto transaction so no, OP.
Since the transaction went through already, I would be more concerned on the current device that you are using since the hacker could possibly more damage which I hope I am wrong. Either do a virus scan or clean install of your device.
Start from there then start implementing 2FA and PIN if you really wish for an extra layer of security.
There is no direct connection if he didn't set a 2fa but if he sets it then there is a connection because before you log on or do any transactions, you will need to enter the 2fa code that will be sent in your mailbox or phone number.
You might be right that his device is already infected by some malware or viruses and it's not safe to use it anymore. He can do some scanning, hard resetting the phone or completely logout all his accounts and transfer to a fresh device and next time he will need to be more careful on what he was dealing with. Who wouldn't want to have an extra layer of security? Unless if he don't care that his funds will get hacked one day (which already happened). I bet he changed his mind now.