That or at least have them say outright, in no uncertain terms, that Agnes was completely under the control of Commodore Oh during that time, because of the mind-meld. It would be a dramatic cheat but at least they would've addressed it and the line of reasoning can work on Star Trek terms. "They did something to her!" As it is, they've just brushed it under the rug completely.
She explained why she killed Maddox. It was his hubris. Lol. The writer really liked that word as he had another character completely unrelated to agnes used the same word as accusation to Picard. So I guess he would deserve death in agnes's eyes. Lol