Chris Vickery identified on GitLab a set of files and data that had been placed there by AIQ. He made a copy of that dataset, and he's given us a copy, but he also discussed some elements of that data and what it contained when he gave evidence to the committee.
What it does seem to demonstrate, though, is the high level of coordination between AIQ, SCL, and Cambridge Analytica, the ability to access and share information in files between those different companies. Also, all of the data that was being managed as part of the Brexit referendum campaign was interchangeable and easily shared. Indeed, at some point, all of that information was made publicly available on the web.
Of course the question is, why was it made available in that way? Was that just a mistake that someone made? Chris Vickery seems to think it could have been a mistake. But, of course, it could have been done deliberately so that the people they wanted to find it could find it if they knew what they were looking for—and Chris Vickery managed to find it.