Why would Jon have any reason to lie to cover his ass? He wouldn't. It's well established that Jon and Chris Christie get along and share some of the same charitable interests.

If Jon gave him permission to use the music to announce his campaign, I see no reason for him not to continue to use it. I'm sure he intends to use the music all along the campaign trail, at least until he gets knocked out of the race. Let's face it... he's not going to be on the ballot in November.