The WGA did not grant a waiver, they signed a contract with Worldwide Pants. If you have a contract, you don't need a waiver, but if you don't have a contract you'd need a waiver to get WGA workers.

And how is any enforceable contract "symbolic?" If the producers let the strike drag on for 2 years, Worldwide Pants would still be accountable to the contract that they signed. There is nothing symbolic about being able to hire any guild writer that you want while your competition is forced to go without writers.