Never confuse skepticism for knowledge. If I claim to have a disability and you are skeptical of that claim, that does not somehow magically imply that I am faking or exaggerating something.
Of course your skepticism is entirely rational and legitimate, and kudos for that. But simple skepticism is not evidence of anything other than some brain’s rational hunger for actual evidence. If you think otherwise you are badly confused. And especially if you happen to work as a disability-insurance claims investigator, then you are dangerously confused and shouldn’t be allowed anywhere near such an insurance claim.
Skepticism is just a first step toward actual knowledge, and a refusal to take the next one — to scrutinize the real evidence — is the most reckless kind of foolery.