ZID HDOF ASSOCIATE CTLR DOES NOT ENSURE RADAR CTLR HAS COORD CTL INFO TO ZME CTLR CAUSING LOSS OF SEPARATION WITH 2 CONFLICTING ACR'S.

Narrative

ACR X WAS AT FL330 LNDG CVG; SW OF PXV. ACR Y WAS AT FL310 SBOUND OVER PXV TO JOIN WLDER 4 ARR LNDG MEM. MY RADAR ASSOCIATE APPROVED A 20 DEG R TURN AND DSCNT TO FL290 ON ACR X. I (RADAR CTLR) WAS UNAWARE OF THIS COORD. I DID NOT HEAR ANYTHING SAID ABOUT A TURN AND DSCNT. ACR Y WOULD NOT HAND OFF TO ZME AND MY RADAR ASSOCIATE WAS ATTEMPTING TO CALL ZME TO INITIATE A RADAR HDOF. ABOUT 2 MINS LATER; CONFLICT ALERT IS ACTIVATED BTWN THE 2 ACFT AND I ASKED MY RADAR ASSOCIATE 'WHAT THE HELL IS HE DOING?' REFERRING TO ACR X. HE STATED THAT 'HE IS 20 DEGS R AND DSNDING TO FL290.' AT THIS TIME ACR X ALT READOUT IS FL323 AND THE 2 MIN 'VECTOR LINES' CROSSED. I IMMEDIATELY CALLED ZME AND REFERRED TO THIS IMMINENT SIT TO INFORM THEM ABOUT ACR Y TURNING HARD R; HDG 270 DEGS. MY RADAR ASSOCIATE STILL HAD NOT COMPLETED THE RADAR HDOF. RADAR HDOF WAS ACCOMPLISHED AFTER THE HARD TURN TO 270 DEGS. ALTHOUGH ACR Y WAS EXPEDITED IN HIS TURN; ANGLE OF CONFLICTION AND LACK OF TIME MADE SEPARATION IMPOSSIBLE.