They probably know this by using the payment systems; perhaps they're online providers of these wallets. This way, they can obtain information about who buys them, investigate them, and plan the theft. That's one possibility I can think of. Now, how they get the money afterward, I don't know. Maybe they tamper with the wallets to extract this data later. I really don't know; I'm just imagining possibilities.
But I assume he didn't do this alone.
As far as I know, this kind of cycle is never one, it may be based on a group. Or it may be that it is his manipulation alone, he has been trying to complete it for a long time. Because it is not that easy to steal data suddenly. The administration should actually look into this matter a little more to see if he has a group or not. Because if those who commit fraud are punished, crypto users will be able to be properly careful in this matter. If they have any influence, they should also be brought under the law. Otherwise, their fraud will continue. And it will also cause a lot of damage.
