It's this simple

This is how active measures works. It's a legitimate process where communication is used to split communities into two, and get them to fight with each other.

Here is an example of how it's done.

In this example, someone casts another person or group as the enemy. They are characterized out of proportion, of course. It's not from a sense of actual upset or outrage. It's just pretending to be outraged, so that the audience will be more and more outraged at the target person or group, as the decades progress.

To say that "86" is sometimes used to refer to killing someone is true. That's the kernel of truth. Then, mischaracterize the situation by stating something which is 100% not true - that a governor is calling for the assassination of the president. It's a distortion of reality - and a pretty obvious example, because the claim is so obviously absurd - but because these statements are said over decades, it shapes the "us-vs-them" dynamics in a community.

Just look up what "86" means to the rest of the world and you'll soon understand that the use of the phrase to mean killing someone is not the obvious intended meaning here. Infinitely more likely, the governor wants Trump voted out of office.

Notice that it's not illegal to pretend to mistake the intention of someone. In normal circumstances, it can be said as a call for peace. In this case, it's pretty clearly - for me - stated in order to demonize the enemy, which in this case is Governor Whitman. And, this is the tricky thing about active measures techniques: it's not possible to tell why another person is doing what they're doing. They can "deny, deny, deny, even when the truth is obvious" and convince their own trusting followers that they are acting in good faith, just as long as they never admit their true intentions.