Wage theft, like any other kind of theft, is a self-incentivizing crime. I agree people shouldn't be allowed to turn a blind eye to systematic lawbreaking, but no system of incentives can erase the fundamental accounting identity that a business unit will have more money if they pay workers less than promised.
It’s easy to to erase that identity. You make the expected value of the punishment (cost multiplied by probability of getting caught) higher than the expected value of the crime.
This should be easier to deal with than most crimes. The problem with individual crimes is that criminals are generally bad at thinking through the consequences. No matter how terrible the punishment is, you’re still going to have murders, because the typical murderer isn’t weighing the cost/benefit tradeoff.
Companies are much better at this, especially big ones. Make wage theft unprofitable and it will drop dramatically.