I may be reading this wrong but this sentence does not make sense.
The ref did make the right decision in real time, the yellow card. This meant anything else meant he did not have to go, regardless of the angle/timing of a freeze frame. This is not the way they should be making decisions, it is farcical to think that a freeze frame alone could send somebody off.
If they showed the tackle from different angles, in full speed, there would not have been any justification to send him off, I mean he might still have because of the incompetence. What they did was purposefully show the freeze frame that gave no context to the force of the challenge or his body position before and after both feet were off the ground. We could show a freeze frame of 90% (maybe even more) of late tackles and they will look like red cards at some point in the movement.