I don't know, maybe its been ruled otherwise, but Mindless seems to imply the model is uncontrolled, except during its activation.
From Mindless:
"Players, in activation order, activate and control 1 Mindless Zombie at the end of the Activation Phase."
"If there is more than one model in melee range, the controlling player chooses which model the Strike is against."
Obviously, you are very limited in what they can do with that control. Other than choosing between targets in melee range, the player really doesn't have any influence on what the model does. Without changing much, the rule could probably have been written in a way that leaves out any player involvement/control, but achieves the same thing.
For example, "Players, in activation order, nominate 1 Mindless Zombie to activate at the end of the Activation Phase...(insert rest of rule here)...If there is more than one model in melee range, the nominating player chooses which model the Strike is against."
That would achieve what you are describing in your post Q'iq'el, and remove any ambiguity as to whether they are controlled by a player during Mindless.