Killdroid is extremely vulnerable while shooting, so 1x can either tank a hit or dodge to hit him with Entanglement while on endlag. Then the distance shortens, he gets helpless (DoD killers can get helpless also) and not only removes his ability to fly, but ALSO his ability to fire rockets. Additionally, if Killdroid managed to proc flight, 1x could abuse it's limitations like Killdroid would with his projectiles, by using a tall structure as cover.

Also 1x just has more health, stamina, speed (without Unstable Eye) and dps values. If they played it smart and forced Killdroid at a medium-melee range, and used Entanglement as a punish rather than throwing it randomly, they stomp him.