I don't see it as a last resort at all.  Suing a handful of shareholders for publicly slagging your company because a bunch of garbage they previously made up didn't come true seems logical to me.  Sculpin is publicly asking Lori to step down, let him drill, save face, etc. because all of his lies have come to head.  He'll wind up with a big fine here soon and will still refuse to admit he was wrong about the whole thing.