Lack of exercise in combination with the prong collar, most likely, are responsible for your dog agressiveness. Particularly, if you say he goes through intensive training. Prong should never be used for training, only for correction of already learned commands your dog isn't perfect with, and even though, you should use two collars - both, prong and flat one, switching from mainly used flat onto prong in a way that your dog doesn't notice it. Prong should never be used on nervous or potentially agressive dogs, as it affects nervous system. If your dog doesn't heel properly - it means that you, as a handler is not much fan for him, some pee on a tree is more interesting. You have a problem of your dog not paying attention to you on walks, if he pulls and doesn't listen. I suggest you to post it as a separate question on this site.
Back to your question with other dogs. Young intact male, full of energy and thursty to explore life, abyss of luring smells, spring odours and young females walking somewhere around, lots of living objects to prey on, and instincts that rip him apart. He is thursty for life. Instead of chasing the ball and tracking 3-4 miles daily, visiting new places and playing intellectual games - you provided him a boring obedience training on a prong collar, when he cannot even pull closer to that tree. Does he run freely? For how long? How much of exercise you provide? If you don't, it leads to extreme frustration, he simply uses your other dogs as scapegoats to to relieve himself from it.
I suggest you to get non-pull harness, a long 7 metre line, and walk him only using that, so, he can go wherever he wants to. Go regularly, as often as you can, somewhere in the woods for 2-3 hour walks with a ball. And do your obedience training during those walks as short sessions. Without any prong collars. In fact, to make your dog obedient you don't need any tools.
You wouldn't solve the problem by separating him from other dogs, absolutely opposite - he might understand it as something special and start looking for a moment to bite. Try to distract him as much as you can, call him to yourself, run away so he would follow you, create a new stereotype for him on your return, like feeding and looking for toys around the house, etc.