Personally... since the filming will be 'officially' done, I'd try to get permission to have an assistant record at or near the board or the position of the camera in photo spodek0085.jpg. Recording from the side like that will be tough 'cause of both the angle between the stacks and being so far off the center axis of the hall.
If it's really not possible to get a better spot, well, for me, mic choice and configuration always depends on what it actually sounds like and what I want to capture / minimize. Ideally, from the side like this I'd guess that I'd want four tracks: a pair of cards for the crowd and a second pair of mics for the band and then remix it all in post.
Since you ask specifically about cards or omnis, I'll assume those are your options. If the omnis sound substantially better than the cards and the hall isn't boomy -- or if you'll be surrounded by audience-singers -- I'd try that. (From 'the charts' I'd guess 80 or 90 cm apart.) If your bass response from your cards is good and / or you're getting echos from the sides or behind, I'd go with the cards and get funky with something like 110° & 50 cm.
I'd set up to get the best recording of the band and just let the audience be mainly on the left channel. If the audience is more important than the band, it's a different situation and the band winds up being mainly on the right channel.
... but, I'm a hack & hoping someone else will have better advice. ;o)