I refreshed my knowledge of waist-height no-ball and see why this was close. As per the laws, an above-waist-no-ball is - "Any delivery which passes or
would have passed on the full above waist height of the striker
standing upright at the popping crease". So, in this picture you have to make two adjustments - one is that you have to "project" him standing upright at the popping crease. The second is that you have to project the trajectory of the ball when it would have crossed the popping crease. The first step will shift the red horizontal line upwards, the second one would move the red circle downwards. It was a close call ... indeed.
Referring to law # 42.6 (b) in ICC T-20 Playing regulations -
http://static.icc-cricket.com/ugc/do...332977_153.pdf