We have had him for a year in April. When we first got him we went through the typically full separation at first then added baby gates while supervised and muzzled, then slowly took away more of the gates to give Aidan more free space, then only a baby gate by the door and no muzzle. I believe they were alone together by the end of the first month. He has always been interested in "watching" Brewski run around but normally never seems interested to get off his bed.
I've pulled out another baby gate and did as other posters suggested and am placing it at the door to his room which has his littler box, cat tree, water, etc. I should of never took it down I just assumed everything was going well. Since the incident everyone has been running like normal and their has been peace and I hope it continues.
Thank you again to everyone who has offered advise, this is a amazing community and the poster support is unmatched.