You are right, that is a rather weak claim in an otherwise very well written article. I especially don't see how higher pain-and-suffering damages would have helped stopping this criminal sooner.
The other factors make it much harder to prove a malpractice case in Texas than in other states, and then the low limit on the damages (which, as the article notes will leave very little for the patient after costs) makes it not worthwhile to pursue the case.
If he could have been successfully sued then after his first two or three botched surgeries his insurance rates would probably be through the roof, and the lawsuits would be public making it easier for the public to learn that they should never go to this guy for treatment.