All I can say “in a nutshell” is that the phenomenology of religion means different things to different scholars; it would be hard for me to predict how this particular professor might interpret it or how he would use phenomenological methods. Basically, it is an approach to religion that tries to take religious teachings, symbols, and practices seriously on their own terms, just as they “appear” (as “phenomena”) to believers, without the reductionist tendencies of the historicist, etc.; this is the sense, I suppose, in which the Schuonian approach to sacred traditions could be called “phenomenological”.
The problem of course is relativism; many—perhaps most—phenomenologists steer clear of objective standards that might help to differentiate between a valid tradition and some diabolical cult, eschewing as a matter of principle anything that might be construed as a cultural or philosophical “bias”, if in fact they do not deny the possibility of objectivity altogether. Religions and cults and sects are all alike, after all, qua systems of appearances, and from the perspective of the “believer” any given belief is naturally treated as valid; in this respect, obviously, Schuon is the furthest thing from a phenomenologist.
Now having said this, let me add at once that if you think the professor is good, it could not hurt for you to learn something about one of the major “methods” in the scholarly study of religion.