Well, apparently coworking is:
Coworking is a style of work which involves a shared working environment, sometimes an office, yet independent activity. Unlike in a typical office environment, those coworking are usually not employed by the same organization. Typically it is attractive to work-at-home professionals, independent contractors, or people who travel frequently who end up working in relative isolation. Coworking is the social gathering of a group of people, who are still working independently, but who share values, and who are interested in the synergy that can happen from working with talented people in the same space.
So it's not as clear cut a dupe of the Workplace as I thought when I first saw the proposal. Still, I don't really think it's a topic with a wide enough audience to support a site on its own, and it is clearly within the Workplace's scope as defined by the proposal's description:
Proposed Q&A site for members of the workforce navigating the professional setting.