I call BS on that statement. I graduated from BJU in 1984 and saw more than one of Tennessee Williams' plays were performed during my 4 years there. I helped produce a student directed version of The Glass Menagerie my junior year and used a dialog from A Streetcar Named Desire in my sophomore platform. As far as Lawrence goes, I remember someone doing an excerpt from A Collier's Friday Night, but I don't remember reading a great deal of his poetry. (Of course it has been over 20 years, I've probably forgotten more than I remember at this point) During this time, BJ III was president and BJ Jr. was Chancellor. There is no way that these plays were used 'behind his back.' Going behind either of the Drs Bob was simply not done -- never, not one time. Unless you wanted to head on home....then you did what you wanted.
I'm not sure what you heard him say, but it wasn't that his institution wouldn't teach Williams or Lawrence because they did while I was there.
He was on Larry King when that anti-Catholic flap erputed a few years ago and I heard him say it. Maybe it changed since you were there. Maybe it changed after he said it.