What caught my eye in that photo, is Bruce is playing a 'Squire' knockoff of a 'Fender' bass. They are a cheap instrument, not to say that they are all bad, but
it just feels like they found a bass hanging around and said 'throw this on'.
That's probably what happened, since they were just miming for that show.
While the "Al didn't know this show was happening until he saw it on TV" story may have been overblown over the years, I will probably never be able to shake the possible image of Al sitting down in the front of the TV with some chips and dip and buffalo wings for his annual Jardine Family Super Bowl Party only to do a spit take seeing this on TV.
The more likely scenario is he just heard about it later; and I'm pretty sure by early 1998, even before Carl's death, Al sensed his days were numbered playing with Mike.
Either way, if I were Al I wouldn't be bummed about missing that cheesy Super Bowl gig. Worse than the "Dick Clark 35th Anniversary" mimed gig from '81, and that was the one where Brian was zonked and Dennis looked to be nearly passed out.