Unfortunately, Harry Fox Agency got out of the music licensing business and no one has jumped in to handle licensing of mainstream music like Josh Grobin. You must go direct to the label (in most cases) or the producer (who often has rights also) and either of them are going to charge you huge sums to use the music.
Harry Fox Agency *used* to have agents with a vast pool of connections in the music world and so they could leverage their relationships and knowledge of the way things work to get you deals. Now, that is left to individuals who are now forced to deal directly with record companies and producres who, for the most part, really do not want to deal with this and therefore hit you high so you will go away and stop bothering them.
And do not think that you can get your client to sign you a waiver of legal culpability as it does not work that way and there have been cases where getting a signed waiver only proved that you knew you were breaking the law.
Sorry to bring you such a dry bone to chew on,
Yer pal,
Cowdog
