The only way to have IVE is if the camera was positioned exactly down the sideline, on this play it wasn't. A camera angle from inside the line "pushes" the picture out. A camera angle shooting from outside the line "pushed" the picture in. The networks, in a lot of games, have the ability to freeze the picture and then zoom in. Some clarity is lost, but it can sometimes be a huge aid for the RO. The RO is charged with NEVER making a decision based on what he "thinks."
If this had been a play in the NFL, it would have been a stands, as they almost never confirm or overturn a call unless it is very obvious the call on the field was incorrect. They almost always try to support the call on the field. In the NCAA, this isn't always the case. And, the decision isn't always made by the RO in the booth. Most large conferences have other officials in a central command center that helps collaborate to deliver the decision.