You can finish your investigation at any time by closing the tab in your browser. Once back to the overview page, you can review your tags and who's investigated which links.
In the top right of the overview page, you'll spot Exports. Click this once you're happy with your tagging.
You can export your findings in a number of ways, as a CSV, back into Backlink Analysis (formerly Audit), or into Site Hunting (formerly Peek). Select your preferred option, and use the options, or rules, to ensure the export is the data you'd like.
You can export your data as a CSV, and then you can upload this directly into your contacts in Outreach & CRM and commence outreach.
You can add and remove rules depending on your tags and how you're managing your backlink profile.
Once you've sent the data back, make sure to use the advanced filters in the Backlink Analysis action bar to show: Links in Investigate list and Links In Approve/Remove List to review your findings and bulk remove links from your Investigate list (which then removes it from Site Investigation).