As usual, the problem with the liberals is...liberals.
As you say in the article, VP Harris could have walked on water, resolved the situation at the border, and passed out free ice cream to everyone in Guatemala and the GOP would rake her over the coals. It doesn't matter what they think or say.
For liberals to be dragging VP Harris over the coals on her first trip is...well, it ain't smart. It's not clear to me why we'd want to risk enraging several of our most important bases just to show how "balanced" we are. It has to be frustrating for women, especially women of color, to see Trump venerated by his party after trips abroad where he stooped to lick Putin's shoes and finagled sweetheart license deals for his daughter's costume jewelry, then to see VP Harris derided, by her own "allies", when she returns from her trip.
All to say...Moscow Mitch ain't our problem. We're our problem.