Notice the "clink" sound at 52 seconds into the video, which indicate that the skill has ensnared the Griffin.
Shadowsnare vs Gorechimera. Victory in 45 seconds.
In the Chamber of Apprehension, against 2 Wights, 6 Undead Warriors and a Gorechimera. Notice the "clink" sound at 15 seconds into the video, which indicates that the skill has ensnared the Gorechimera.