Seating chart during ceremony -adoptive parents/birth parent additional plus parents

My soon to be husband was adopted at 5 years old. During his teen years he had a difficult time connecting with his adoptive parents. He meet a man who has become a second father at 17. (My bf is 43 now) Fast forward to his mid twenties he connected to his birth mom (who has many issues and causes problems) his best friend since his teenage years has died and his mom as taken him in as her other child. He has sense created a healthy relationship w his adopted parents after years of them being distant. I am come from a family that my parents are still married and it’s not complicated on how to do my seating during the ceremony. How should I do the seating for his side regarding parents. (His birth mom thinks she should only be the only “parent”) again here is his “family structure” : Adoptive parents-birth mom and husband -second dad who is more like a any parent/dad in his life, his bff friend mom and her husband. I guess my big concern is his birth mom throwing a fit if she’s not recognized as his mom and walked down the aisle or sit in the first two chairs. HELP! Lol