Minthara cannot be spoken to after being taken to Moonrise Prison. You said this was being investigated but it is still there. Also so is the disappearing dice roll window forcing a reload until it fixes itself -.-
I hit that problem with Minthara also, but by choosing different talk lines with the interrogators, managed to get her out of the prison. My hunch is that she's unreactive because a cutscene with her didn't complete properly. See below what worked for me.
