Dwarf Bi Color and Maroon Clown Agression

I have a 45 gallon reef tank (started as a reef tank before my Bicolor Angel decided to eat most of my corals). In 2012 I only had in it the Bicolor angel. I added a 2 inch maroon clownfish and the bicolor started beating him up. After some recommendations on this site, I introduced 2 brown damselfish about an inch each. One of the damselfish took over dominance of the tank and kept everyone under his control. Killed the other damselfish but managed to keep the bicolor and maroon in line- each one in their respective "boxers" corner. All three have co-existed in my tank for over 4 years. The damsel got to 4 inches- the maroon to 5 inches. Well about a month ago my damselfish tragically died caught up in water polisher contraption. Since then I find that the bicolor has 2 bite marks on its side. The crazy thing is that it looks like the bicolor angel goes and provokes the maroon clown. It does not hide or act meek, it eats fine and swims all over the tank. I find him going over to the maroon clown and shaking his tail at him- looks like he is asking to get bitten. I do not have another tank to separate them. Should I re-introduce a 3rd aggressive party to this mix or keep my fingers crossed and have them settle down. Both have been in the same tank for over 4 years.