Ch. 500 Jidanbou and Rin acting strange mystery

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This has been tormenting me for a while, so I thought I'd just bring it up: in chapter 500, page 10, Jidanbou suddenly attacks the Research and Development Department, next Rin, who was acting normal a second earlier talking to Ichigo, stabs Hiyosu. It is obvious they are not acting of their own will, but does anybody have a theory on who the guy controlling them might be, or at least what race? His leg can be seen here in the first slide of page 12 but does it look like Quincy uniform to you?