At this point Danny should start to seriously consider sending Wallace and two first round picks to whoever will take him for an expiring contract.
The last thing a new coach needs is a disgruntled vet in the ear of impressionable young players. And given he has three years on his contract, he could kill a good young player's outlook on the league and the franchise in that time.
Don't need him. Pay the price and dump him.
Cheaper to make an example of him and bench him until he learns his lesson. I wouldn't play head games with him. If I were Stevens I'd have a talk with Danny and hopefully call Wallace into the office and tell him he's reached his limit for complaining to the media for the year, and in the future if he has problems with anything to say it to Danny/Stevens and not anyone else.....or go home. You do not have to like it. When you become a coach...which is a possibility given your history of effort and attempted leadership...you can do what you want, but not now. We understand you're a vet and have done your best and have earned the right to say stuff a bit, and you did, but that time is over now, and we can't have dumb young guys thinking they can do it, because they can't, but they don't even know that cause they're rookies. Now that we're here do you have any problems we can address?
In the words of an actor that portrayed Steinbrenner (I can't find evidence he said it) "I do not pay them to be happy"