Well as I see it Glyph is really the only other person than Bern in a position to do anything: (Excluding Fata and Moss but they don't really count yet, there isn't any kind of loyalty or anything here)
May is down an arm, and while she could probably do some damage still, she's not in costume therefore useless right now.
Crest, Meatshield... not much else to say, but if he moves and tries to fight, he'll it'll leave him Most likely in Bern's way and leaving Bern to worry about May, so he stays a meatshield.
Suspiria was not only leeched of presumably most or all of her essence, with little or no time to heal from it I would assume, during her confrontation with Danzig. Not to mention her little meeting with Melter (
http://www.flipsidecomics.com/comic.php?i=926 ) where who knows what happened, if anything. So it's fairly safe to say she's useless as well.
And that leaves Glyph, and while it's rather safe to assume that he's on their side, who knows what's going on his head. Maybe he's aware that using magic right now might get him drained, who knows. Maybe he's waiting for some kind of opportune time.
Or maybe everybody is jumping the gun and Brion is just building suspense and depth before having people do things, and so he doesn't have to cram an entire battle into 3 pages.