Background: Area 51 has recently gone from using comments for each proposal to a site-wide discussion format.
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The question you linked to was correctly closed - you need to drum up support for the proposal elsewhere.
As for your question about the name I don't see why it can't go on the discussion site. You are, after all, discussing the proposal. However, I'm not in charge of the system and the process so treat my answer as an informed guess rather than the "truth".