Yeah hate to spoil the party, but this is not 'wage theft'. Wage theft is very specifically the act of withholding wages that an employee is entitled to according to the terms of his or her employment agreement. What happened here is not even 'price-fixing', it's a fairly weak attempt at 'collusion'. Yes, it seems improper at first blush and the email exchanges are almost comically incriminating, but my guess is that…
"a) never cold call each other’s employees; b) notify each other if making an offer to an employee of the other company, even if that employee applied for the job on his or her own without being recruited; c) any offer made would be “final” so as to avoid a costly bidding war that would drive up not just the employee’s salary, but also drive up the pay scale of every other employee in the firm."
I think it's clear how this would affect wages.