Today my normally peaceful flock was not so peaceful. Oliver has always watched over Albert and Russell just accepts him. Neither would reciprocate Albert's attempts to preen them or have them preen him. Today, Oliver and Albert started to feed each other, preen each other, and Oliver will chase Russell away if he comes near them. Just this morning and afternoon, they were having their conversations! Russell has no idea what happened, I'm sure. He keeps trying to just go hang with his friends and Oliver won't have it. I feel horrible. I separated them and put them back together with their oat plants that they have to open the pods and then get to the oat groats and they are all peacefully eating. I'm going to get a friend for Russell. Male of course.
I'm not surprised that Russell has been relegated to "third wheel".
When I had three males there always seemed to be one that ended up getting left out.
Even numbers seem to work best.
My suggestion would be for you move Oliver back with Russell since they get along well together.
After the new baby is fully weaned at around 8 weeks or so and you bring him home
and finish with quarantine, he and Albert will bond easily and become best buddies because they are closer in age to one another.
I have a similar situation. I have 5 and thus my oliver is the odd bird out and i can tell he is lonely for the other 4 paired off. But The other boys will periodically spend time with him which is good but i can tell my oliver is lonely when the other 4 preen one another for he gets ignored. I have considered a second cage for mine and buying him a friend as well so he will not have to be alone