A Center Controller reported airspace delegated for a military UAS was not activated as scheduled and the UAS flew through Center and TRACON sectors uncoordinated.

Narrative

This was one problem of many going on in this sector at the same time. There was a safety event in the South Area which affected multiple sectors. A drone inbound to ZZZ; was at 51000 ft. southbound from Sector X; through Sector Y and into Sector Z. The controlling agency was supposed to activate a Descent Cylinder using the Warning Area. The drone was intended to fly to the point within this cylinder and descend safely to 14000 ft; then fly into ZZZ approach. None of the above occurred. The controlling agency told our frontline and Traffic Management Unit (TMU) that they thought the mission had been canceled and then refused to activate the Warning Area.The drone paperwork was incomplete and didn't include the pertinent information should the drone go 'lost link.' ZZZ Center airspace approved the drone to arrive during peak air traffic levels. Multiple aircraft needed to be vectored to avoid the negative RVSM drone. The drone was unable to take vectors and the drone operator stated that the drone will fly the pre-programmed route. We needed to call the adjacent ATC facility ZZZ Approach and advise them to move everyone out of the way because we didn't know where it was going. In short; the controlling agency should have been aware that the Drone mission was not canceled. Then when they realized that it was inbound; instead of throwing up their hands; the controlling agency should have activated the sterile Descent Cylinder. Additionally; ZZZ Center Airspace did not provide TMU or the South Area with the proper information regarding the drone and more importantly they allowed the drone mission to be filed through one of the busiest times of the day. Recommendation: Better coordination.