And what evidence do you have that this May 14th disclosure has nothing to do with Wyden's March warning? If you remember your history you'll know Wyden tried to shake the Snowden revelations out before the Snowden revelations.
Dismissing Wyden's remarks as "american politics" is near equivalent to dismissing the entire notion of VPN security.
Mullvad has explicitly given their reasoning. That's the evidence. Now the burden of evidence is on you to show that these things are connected since you are the one challenging Mullvad's claim.