As far as I understand, the only difficulty with Discourse is that having a Farset-branded forum for this encourages people to come to Farset with tech requests. If that's not a problem, then the Jobs board seems perfect, but from the Slack discussion I get the impression we want to discourage that association.
If not Discourse, then something off-site - given the target demographic is non-technical people who are looking for quick fix (on the assumption that anybody more motivated or informed will use the Job board), then they /probably/ have a LinkedIn account and are used to using it. This would, naturally, become noisy, but would beat simply telling them to clear off.
Digital Circle is also an option as a digital connecting space, so it fits in their remit, but it sounds as if they are already directing these types of science and engineering enquiries to Farset.
My only personal feeling is that, as I am in the coworking space quite a bit, it would be helpful to have some SOP that we can stick to when people ask - the One True Established Way of not hassling NEMs, directors or members - so eventually when someone in Uni A asks technically minded Uni A member Techie B, Techie B says go to the OTEW (not ring Farset and leave a phone number). Similarly, with such enquiries DC that directs to Farset, for that matter.