I suppose your right... If my kids attended that school, why wouldn't I want them being led by ("Any overlooking of Christ and Christmas was inadvertent, they said.) liars.
Well, if your child attended the school, I presume you would know ahead of time what the program would entail and would have made your thoughts on the matter known. If you were then informed that they prohibited Christmas songs that mention Jesus, THEN I would say you had a complaint.
So far you're over-reaction appears baseless and nasty (not the image I would guess you are seeking to present).