It is more beneficial to offer positive feedback, and positive solutions, rather than bash him for getting this breed. He has them, now he needs guidance on the best way to work things out and manage a multi dog household. Most people would say I have no business owning 6 dogs of various breeds, but I do... and from time to time, I have questions and need suggestions on what to do with different situations. If all I got was bashed for owning my dogs, I wouldn't come back to ask questions.... thus, I wouldn't be learning anything beneficial from the site. Remember why we are here, to educate and HELP, not to bash.
Well it sounds to me like you have no business owning ANY pit bull, much less two. What kind of bright idea is throwing two bully breeds who've been around each other a week into a "play tug of war" and share toys situation. It's like you are trying to ensure a fight. Every fight that you allow to happen, is one step closer to full on crate/rotate and somebody getting hurt. And if you can't stand the idea of them not getting along someday, then why did you pick this breed and get multiples? You want your dogs to get along, stop throwing them into those situations and get control over them.