First, a disclaimer that I have not read beyond the first page of this thread. So I won't know if I am duplicating any suggestions.
Next, I do have lots of experience keeping multiple roosters, and have come to notice the younger ones seem to have more of a penchant for testing rank. Currently, I have two aging roosters, seven and eight years old. When they were young, the squabbles were much more frequent than they are now. And since the younger one challenged the rank of the older one two summers ago, reversing the roles, there have been no more fights. But they had a built in rank from the beginning as the younger one was introduced to the older one as a young chick. Cockerels of the same age will not have this built in governor.
My guess at what's going on with your two young boys is they each are vying for the role of head roo in view of having neutralized the older rooster. Sometimes it takes time for them to agree on which role they will each assume. And springtime hormones do play an important role. I would try to be patient and let them try to work this out between them. Yes, it will likely result in some injuries. Keep a close eye on them.
Years ago when I first joined BYC, there was a young man here who lived in Olympia WA and ran a rooster rescue in a homeless encampment. He had his own tent and another tent for about twenty roosters. He was also a chicken psychologist, and wrote extensively on rooster behavior. I learned a lot from him. His writings are probably still out there.
Having upwards of two dozen roosters in close quarters required that the roosters learn to get along. He was an expert at training and disciplining them. Most of them responded quickly and got with the program just fine. But occasionally, someone would bring him a rooster to join his flock that felt compelled to pick fights with another roo. When all else failed to convince the two birds to make peace, he would install them in a crate together. Not a large crate, but one where they were forced to be in constant contact with each other.
You would think that this would be a recipe for disaster, that it would turn into a blender of blood and feathers. But the result was just the opposite. More than learning to make peace and tolerate one another, they established a close bond due to the intense proximity. The length of time required to do this varied from a couple of days to a week. But the result was that they became inseparable.
Something similar has been reported by other members when they have a hen that requires intense one on one treatment for serious illness. This is often a hen that refused to have anything to do with their human flock keeper prior to the illness. After the intense interaction that day to day treatment requires, the hen will have bonded so completely with the human that they completely changed from then on to being the biggest fan of that human. So it must be a trait chickens have, or at least some of them.
If your boys continue to have an unresolved agreement on how they will handle their relationship, you might try crating them together and see what happens.
Here is a link to the writings of that Olympia rooster rescue guy. He's made a lot of fascinating videos, as well.
http://olychickenguy.blogspot.com/