The controller clearly told Key Lime to hold short of runway 24 left and he made sure to emphasize the "short". The pilot acknowledged it and it may be hard to explain that away to the FAA.
There are specific paint stripes on taxiways that cross runways. Pilots taxiing up to runways see the stripe pattern, and must stop and get permission from the tower to cross.
It's hard to imagine someone knowing they're about to cross an active runway and being so unaware of where they are while an Airbus 321 is bearing down on them.
She may have seen the departing Delta plane rotate and figured there was plenty of space and started rolling, but should have waited until departing jet was past the taxiway and is required to wait for the tower to give clearance to cross the runway.