If he had really been a Catholic his whole life, he would have known that there aren’t any invited musical acts at a funeral Mass, or any other Mass. The actual music has to be church approved.
The Father told him that he can’t change the Liturgy, and gave him options to sing elsewhere.
As one Catholic friend told me, they won't be satisfied until they can have a clusterf*** around the altar and have their fake marriage blessed by a priest. Maybe not even then.