Saying something that isn’t true isn’t necessarily a lie. I used to tell my grandmother that she was the best cook ever. That wasn’t true, but it wasn’t a lie. My grandmother knew it wasn’t true, and she knew I didn’t really believe it, but that didn’t make it a real lie. It was a white lie, or, more precisely, bullshit.
A real lie is when you deliberately tell a falsehood, with the intention to deceive.
Trump didn’t want a pointless public confrontation with Trump, so he refused to acknowledge that the Russians were messing in our 2016 election. He refused to call Putin a liar to his face. That wasn’t a lie. It was a useful diplomatic fiction.
Treason is what the Mueller/Rosenstein cabal did when they tried to set President Trump up. By coming up with their indictment of the 12 Russians when they did, they were setting up the question which Trump was asked.
Why? What were they trying to accomplish? They wanted to blow up the summit. They wanted to interfere with the President of the United States as he makes and conducts our foreign policy.
That sounds like treason to me.