In my opinion, if the parts to those songs are now in a Jewish context, then there is no problem.
If you think about it, how much of music is truly only touched only by Judaism? Even the notes of the scale; unless discovered by a Jew, can we say C, D, E, F, G, A, and B are “treif”?
If music was used to entertain idolatrous kings, then should we listen at all?
Suppose the first musical instrument was created and played by a pagan for some sort of worship? Do we not touch musical instruments unless they were invented by a Jew?
I also understand there are tunes we use in davening that did not spring, 100%, from the Jewish well of culture.
If the entire CD is now in a Jewish context, then musicians and song writers are using parts of the song for music only.
Your concern is valid and thought provoking and does not end with music. It carries on to clothing (should we not be wearing robes since the suit was not invented by a Jew, perhaps?, household items (I think it is worth investigating which companies were involved in the holocaust, and these things are known, but how many Jews own things from autos to coffee makers to countless other things which originate not only from the gentile world, but from antisemites).