I am curious about this as well.
When I read "voting ring" I think of accounts trading votes - a group of accounts votes for each others' stories.
But your description (possibly accurate) is that asking people to vote for a story is a "voting ring".
Once in a while my company makes an announcement of some kind and emails that announcement to some portion of our customer base. Sometimes that announcement includes a link to an HN story that I create with an invitation for discussion. We never make any mention of voting or scoring.
This makes good sense because we don't have a forum and everyone prefers the HN user interface anyway.
Is this a voting ring ?
If this is not a voting ring, per se, is it likely this still trips the voting ring detection ?
Is this poor HN etiquette ?