As I recall, there wasn’t a problem with Happy Birthday until “Sir” Paul got a hold of the rights. The Marcarena guys did this with the Girl Scouts as well.
Paul McCartney has bought a lot of song catalogs over the years, but he never owned "Happy Birthday." The small publisher that owned the rights was bought out by a Time Warner subsidiary in 1998.
The Marcarena guys did this with the Girl Scouts as well.
I don't doubt it. If the Girl Scouts were making the Macarena song part of their events, it's only fair that they should pay the people who created it. It's not a lot of money, and it's negligible when spread out over a large organization like the GSA.