Perhaps it would do you well to read for comprehension before blasting off. No one said the Church (as in the whole Roman Catholic Church). Here is what was said:

Shortly after the 9/11 attacks five years ago, a number of highly public funerals (e.g., for NYC police and firefighters) featured the singing of "Danny Boy," or at least the instrumental performance of its melody, also (originally?) known as "The Londonderry Air." The Roman Catholic Archdiocese of New York, along with some but not all other US dioceses, responded with a ban on the use of this song at all Catholic services, because of its "secular" nature.

The parish you were in very likely did as you say, but I will bet a fair amount of money, a harp I don't like anyway, and toss in a cat that I don't like either, that it was not within the context of the Mass, but after Communion. No one said the Vatican issued an edict.

Hop off the horse.

Mick