I assume you are referring to stories like this[0] where the UK's Information Commissioner’s Office (ICO) recently found that "Cambridge Analytica models were exaggerated and ineffective". Presumably you don't think that there could be any bias in the ICO's investigation, despite the UK government now being run by Boris Johnson, Michael Gove and Dominic Cummings, all senior members of the Vote Leave campaign group.
Regardless of any bias, there is the question of whether the ICO had the data it needed to judge CA's models sufficiently. We have a whistleblower claiming that Vote Leave "attempted to destroy evidence"[1] and photographic proof that "Storage crates were removed from Cambridge Analytica's London headquarters today (pictured) but it is not yet known who has ordered them to be taken away"[2]. In fact, CA were given at least a week's notice to prepare for the search warrant[3], a privilege not afforded to most criminal suspects.
You might think that there is nothing suspicious about all this, and that even a fair examination of CA's practices would clear them of any influence over the outcome of the referendum (and you may also think that all online advertising is a waste of money, because it can't influence people's decisions and opinions), but please do not glibly state without a citation that the story about them is "unravelling".
[0] https://www.itpro.co.uk/policy-legislation/data-protection/3...
[1] https://www.theguardian.com/news/2018/mar/26/the-cambridge-a...
[2] https://www.dailymail.co.uk/news/article-5521893/Warrant-sou...
[3] https://eandt.theiet.org/content/articles/2018/03/informatio...