How do you know how bad their ADHD is?
That's the whole point of the different types of accommodations. There is no one-size fits all. Time extensions, for example, are rare, because LSAC has experts who look at the disability and the seriousness of the disability and make a judgment call about what kind accommodation is required. Double-time extensions in particular are almost never given.
This diagnosis is abused, and will continue to be abused if there is an incentive as in this case.
It's like you think that someone with money can just hop on over to a doctor, get a diagnosis for ADHD, and without having any demonstrable symptoms or issues with ADHD in the past just hit up LSAC with the diagnosis and, presto!, LSAC will just give the doctor all benefit of the doubt and the applicant gets a time extension, no questions asked. That's not how it works.