Have you found that lower quality citations help bring more traffic? If the citations are so hard to find that they don't show up in either of these 2 databases, my sense is that they aren't of any value. If you want a more robust backlink checker, I'd go with Ahrefs.
Have you checked the Google My Business Tab inside Brightlocal? There you can find more citations for your relevant keywords that you added to a report. Especially industry relevant citations can be found in the competitor table.
We hired a link builder who has tons of press connections. I think good PR is one of the most effective ways of link building because you can get quoted or mentioned when reporters are looking for someone. I think it becomes more manageable if it's the main task that the person focuses on. HARO is a good place to start if that person doesn't have a lot of connections already.
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