According to their website:
Catholic Network of Volunteer Service (CNVS), established in 1963, is a non-profit membership organization of 200 domestic and international volunteer and lay mission programs. Currently, more than 10,000 volunteers and lay missioners serve in these programs throughout the U.S. and in 108 other countries.
At their website they announce that Chris Matthews will be the keynote speaker, but you know, they never mention that he is both pro-abortion and pro-gay marriage. Amazing how they missed these things, which are easily found in a search about him. But maybe it does not matter to them. Why would a Catholic group have as a keynote speaker, someone who views the killing of unborn children morally acceptable. Maybe Catholic is just simply a placeholder -- a holdout from earlier days.
Now,don't get me wrong. The objectives of the organization are good, but must they honor someone who stands in opposition to some key Catholic values?
So, if you decide to write to them, and I urge you to do so, be respectful and ask that they pull back their offer. I doubt that they will (they are located in Takoma Park -- that explains a lot).