Hi Lynn,Christ is the head of the church. I wouldn't worry to much about affiliation except with the Lord! However, you say "he" is not under any body & "he" serves wine. Does he act as a one person show? (ICPreacher type) Or do all of you participate?
As for real wine or any other area that you disagree with this person, I would head home to my prayer closet. You may want to skip fellowship with this person a week, two, or how ever long it takes for you to settle things in your heart. Pray & study the issues at hand again. Be convinced in your own mind what is right. Seek the Lord's voice on which things to leave fellowship over & which to overlook. Then either return to this fellowship or continue at home yourself as the Lord leads.
We once went to a small church that served both wine & grape juice because of the belief of one person. Another family in this group decided that the woman should wear a hat. Some did not want to eat pork or unclean meat. We did not bring such food to potlucks for the sake of the others, so as not to offend them. We did not feel that these things were things to leave over; but let each person be convinced; as each would stand before the Lord in judgement one day.
Faith