I would think if they're close enough to taser, they're close enough to use a 'tranquilizing dart'.
They probably didn't know what chemicals she had in her at that point, as well as not knowing her weight for dosage.
If she had died, there might be some news value to this report; but she didn't, so why does it matter how she had to be restrained? What's the acceptable weight of biting, kicking people for tasering? They must've used a low setting, if there is such a thing, since they still had to restrain her afterwards.