>>> She can only be recruited once by any army, including Red Blok GenCol and Cogs
I would guess this means there can only be one copy of the hero per army. Gencol can have multiple copies of the same hero, but Francesca isn't Red Blok so Gencol can't clone her. The Cogs, presumably, can do similar things. I think you can still use her. I'm prepared to be shot down in flames 'cos I don't really know anything about her.