I had a player like this in one of my campaigns. He was playing a paladin, supposedly a sound battlefield tactician, but he himself was pretty clueless. After he mentioned that he was getting frustrated, I suggested that maybe once per encounter I would offer some tactical advice, or he could ask for some advice, which I would give purely to his benefit. I was always careful in my advice to point out the benefits and disadvantages of certain actions, such as "moving here will open you up to sneak attacks from all 4 rogues, and may very well kill you. If you move here instead you can still attack and protect the party, but you are much less vulnerable." But I still left the decision to him. It worked well, and he was much happier from that point. In fact, he began to learn from the advice and toward the end of the campaign was making sound tactical decisions on his own.
In your case, you may suggest something similar, given that the characters are probably decent in tactical combat, even if the players are not.
In your case, you may suggest something similar, given that the characters are probably decent in tactical combat, even if the players are not.