false teachers

A Facebook friend recently brought to my attention an example of what appears to be a false teacher, a western woman by the name of Marjerie Dadak who is teaching under the name Domo Geshe Rinpoche.  Here is a link to her website

Domo Geshe Rinpoche was a lama of the Gelugpa tradition who died in 2001.  One her web site, Ms. Dadak claims that upon his death, his mind stream was transferred to hers and that she is now the legitimate "reincarnation" of Domo Geshe Rinpoche.  The Gelugpa have not endorsed this claim.

For a brief biography of the lama who died in 2001 see Domo Geshe Rinpoche .

So the question is raised, can a teacher with questionable credentials actually benefit his/her students?  My Facebook friend wrote,

Suppose someone decides to fraudulently pose as a medical doctor. And  all  they dispense is advice, based solely on the works of other licensed medical doctors. Patients get better and recover. Some get worse and seek other medical help. When this person is exposed, does that invalidate the health of those that got better? Of course not.

So I am at a crossroad as to which direction to go. On the one hand, yes get this Marjorie off the circuit of spiritual frauds. On the other hand, I am stuck until I can come to terms with the fact many have found spiritual health from her. And what of them. Do I need to crush their loyalty? Of course not.

I responded:

The advice one receives from a doctor applies only to this lifetime, whereas the advice one receives from a qualified spiritual teacher applies to all life times. The consequences of following a true vs. a false teacher have enormous karmic weight.

Therefore the qualifications for being a true spiritual teacher are much higher than a medical doctor. This also explains why finding a true teacher is so difficult.
Since no one can tell when death will strike, it is better to not waste time with false teachers.

But again, where does the responsibility of the students of the woman in Wisconsin lie?  Do I have a responsibility to help expose this teacher (by writing this blog entry for example) or is it better to say nothing and avoid spreading conflict?