Probably the best you can hope for is that they will tolerate each other as long as there is some distance between them. My three birds, a grey, a sun conure and tiel do not get along but they tolerate each other as long as one does not tread too closely. I would have liked for them to get along together but that is wishful thinking, I imagine that most of us with multiple birds have this problem to some degree so you have plenty of company in this aspect.
I see in the first pic that they are sharing a perch, you might be better off to keep them on separate ones so there is some distance between them and see how it goes but you are still in the early stages with your new grey.