Mistakes are made daily by pilots and controllers, they are of course usually sorted without harmful effect. It is not on to pillary this controller or the ATC agency who are only part of the tragic course of events, if the Rusian crew had responded to the TCAS then we would have had a near miss and we have those not infrequently. Simple fact is that TCAS has prevented a significant number of conflicts it hasn't caused any and most of those it avoided were the result of human error, world wide.