If Cortez had asked, that would have indeed been the answer he would have gotten. No one had asked, and if they didn't ask, Arkhah wasn't concerned. While he had never worked for a Tau employer directly, his people knew the grey-skinned race quite well from their long association, and knew well that the Tau did not do subtle very effectively. They could employ subversive agitation immensely well, and had technological stealth equipment that put Arkhah's natural chamelonism to shame, but thoughts of infiltration and sabotage simply didn't come naturally to them. He was under pay to defend Cortez and his interests from danger, but as long as the Tau were keeping to themselves, he had not classified them as dangerous. They would reveal themselves and their agenda in time, or else be found out - as they now had - and then he would be able to reassess the situation.