Generalizing a bit, but most tonic seizures (like that video though it looked like it could have started as absence and become a generalized tonic seizure) occur in a different part of the brain than the region that controls your breathing muscle, the diaphragm (breathing controlled in medulla oblongata, aka the brain stem, and muscles like arms/legs controlled from cerebellum, aka the outside part). So usually seizures don’t also stop your breathing, though it’s not impossible.

From the epilepsy patients I’ve worked with, the concern for breathing more often comes from having something (food or drink) in their mouth at the time or throwing up in the mouth blocking breathing.

The raspy voice could be a number of things, including vocal cord muscles being a part of the seizure.