Last year one of my competitors had page one and ranking #1 in all major cities in all keywords. Well he may have went out of business. I don't know for a fact but he let his website go and ..Yes I have control over it.
My question is since it has went off googles radar for almost 9 months now how can I use this to help build my ranking up?
Rebuild the pages from his website on the domain.
Use a tool like Ahrefs to "Best by links" to see which pages he had built on the site.
Use archive.org to research those pages and see what optimization he had in the URL, page title, and on page.
If the site is not indexed, submit it to search console and track the rankings for keywords to see if Google starts ranking the site again.