Or you could create a feat that grants an offensive version of uncanny dodge. IE, instead of retaining dex bonus, you retain the ability to make AoO.
As for avoiding the "mind control" ability of the knight I suggest interception and dynamic action to allow a defender to prevent attacks against allies. This allows one to actively defend by foiling the actions of others rather than forcing them into a specific course of action.
Interception: an attack that begins, ends, or passes through the area within 5 feet of you can be intercepted and redirected to hit you instead of the intended target.
Uses: Stop adjacent enemies from attacking distant allies, stop adjacent allies from being attacked, provide a "wall" of flesh against ranged attacks.
Limitations: You get to take damage, joy. The good news is that a defender is likely to have a higher AC and possibly DR than the original target, so it might not be so bad.
Additional limitations: perhaps it counts as an AoO? or an immediate action? or perhaps you need to sacrifice actions (swift?/move?/standard?) before you can use it. Or perhaps there are limitations on the number of times per round/encounter/day that you can use it. Whatever the GM feels appropriate for the ability.
Dynamic Action: you may take actions during the turn of another character. Unlike a readied action, this has no specific trigger.
Uses: move to place yourself between an ally and a charging foe, move to give cover to an ally subject to ranged attacks or reflex save effects, attack a spellcaster as he moves or casts a spell, move out of range of a foe as he attacks you, etc.
Limitations: You have to sacrifice actions to get dynamic actions.
Additional Limitations: Depending on the specific rules, you may have to sacrifice larger or more actions to recieve dynamic actions (Full round -> standard, standard -> move, move->swift, etc.) Or have limited uses per encounter/day. Again, whatever the GM feels is balanced.
IMC: Interception is gained through a feat, and can operate 1/round. Also once per encounter you can use it once more in a given round. Also once per day you can use it once more in a given round. Additional feats allow additional uses.
Dynamic Action is gained through a feat, one sacrifices a FRA to gain a dynamic move action. A second feat reduces this to a standard action, a third feat reduces the cost so that move -> move. This only works for move actions, not standard actions.