I am an American teaching at Peking University in a field unrelated to architecture. I was recently asked however by the Dean of our campus if my wife would be interested in teaching architecture. My wife received an acredited 5 year BArch more than 12 years ago, did IDP through NCARB, and is AIA licensed. Can she teach at the university level? I cannot find a clear answer for that and she doesn't know. Some schools seem to compare such a degree to a MArch but we wonder if she can teach at the university level.
First, your wife is not AIA licensed. An architect is licensed to practice by the state in which they applied. The AIA is a membership organization.
The answer to your question is YES. An individual, regardless of education and background, can teach architecture if the University deems that individual qualified. You are correct that most U.S architecture programs either require or highly encourage a Master of Architecture as a minimum qualification to teach, but there are still current professors that only have a BArch like your wife.
I would suggest that she go for it if Peking wishes to hire her and she feels qualified to teach.