Let me see if I understand, basically Fisk's lawyer (probably still Ben Donovan) used arguments such as, since there was no physical evidence against Fisk, only the video recorded by Agent Nadeem, who was killed by Bullseye, and the FBI agents and Hattley testifying against Fisk and in favor of Nadeem's video. Fisk's defense alleges that most of the corruption perpetrated was mediated by Hattley, placing the blame on her, making Fisk appear to have been used (which isn't the case, but there was no evidence beyond testimonies), that Nadeem's video was ordered by Hattley to blame Fisk. Fisk's defense said that Hattley and corrupted FBI agents made Poindexter, who was a FBI agent, to use Daredevil costume to incriminate Daredevil, which of course not true, Fisk did. So the case becoming so compromised that: acquittal (or dropped charges) becomes inevitable, in the process acquitting Fisk and Vanessa, and maintain arrested Hattley and the FBI agents, also Bullseye, because he have mental problems, so he stayed in mental institution instead. That's why Vanessa tells Poindexter, in Born Again S1 flashback, that it was because of the FBI scandal that Fisk was acquitted. So when Vanessa says: "The whole FBI corruption scandal… it's why my husband was acquitted". She doesn't mean: "It proved he was innocent" She means: "It made the case impossible to prosecute cleanly".
Does this all makes sense?