Well, no. Musicians wear headphones or earpieces (what are called in the business "in-ear monitors") specifically because they can't, and don't have to, hear the main ("front of house") speakers. The other approach is to use monitor speakers, but it's the same thing: the performers are hearing that mix of sound, not what the audience hears. The engineers' responsibility is to give the monitors the mix the performers need, while giving (and in an event this big, these are different engineers using different equipment and probably even working in a different location) the audience a completely different mix that works for them.
Really there's no reason to use pre-recorded tracks and lip sync in this kind of performance except that they don't want to take a chance on it being less than perfect. So, record the track in the studio, multitrack the vocals, add whatever effects are necessary... and you don't have to deal with all of that live.
Yeah, I've worked for years as a live audio engineer. In fact, two of my friends were on the Super Bowl crew.

