who was highly conflicted

Saying one is "conflicted" normally means they are confused because they are torn between 2 ideas, choices, etc. Like there is a conflict going on within oneself.

Not really sure what the author of your statement is meaning here, since it's pretty clear he's calling Mueller a Trump hater and nothing else. Doesn't say what else Mueller is conflicted over.

I'm fairly sure the writer, unless an explanation can be given for what he meant, the phrase is not being used correctly.

This is referring to Trump feeling that Mueller had “conflicts of interest” and should not have been conducting an investigation.

Trump wrote the tweet.

Yeah.

I was gonna say to orister if it's a tweet written by Trump, don't count on it making much sense.

He has the writing skills (and speach patterns) of a third grader, if that.

Agreed, it was a poorly written bit. Not having the readers understand your point is an area that should have been caught by the editors. Lotsa papers are killing their editorial depts. I love to catch some really funny headlines that were obviously rushed to print. I see em more and more and more.