Highly unlikely? You've already determined there was no negligence from the pilot ? I assume you've written to the police then with details of your findings.
For me, given the sad state of my CPS politics, and how they answer the tests of whether it is in the public interest to have a prosecution, and whether they think they can secure a conviction, I personally would not be surprised to see this end up in both the civil and criminal courts.
And no, I have no evidence about the tragic event to say what the cause was. So my mind is open as to the eventual findings, but the preliminary AAIB bulletin suggests no obvious problem with the plane.