Some weird bug? wukong ult flash doesn't apply knock up or damage.

If you watch the video, note that when I flash on caitlyn while spinning. You can pause the video in time to see that she is just standing besides me after I flash on her. Because the knock up didn't apply, she could easily flash away to avoid death.

I tried it again in the practice tool but both knock up and damage were applied the right way; nothing strange.

Does anyone have similar problems?