I'm asking if that's called lying. When a team signs a player for $15 million, but then calls $5 million of it a "bonus" for signing the contract, so they can get around CBA rules, are they lying? Does the commish not notice or care?
The $5 is still considered income for the IRS. So yes, it would be lying tax purposes but perhaps not for any fees due to MLB
The CBA is a negotiated agreement between the sides so they can decide to count what they want, and they decided (explicitly or implicitly) not to count bonuses. You don't get to negotiate with the government.