Can An Employer Deny Ada Parking

Like the title, can my place of employment deny me ADA parking? I have a (TX) state issued permanent placard, due to knee and hip issues diagnosed by the VA.

My employer is requiring their own vetting of my medical conditions in order to get a medical pass on top of my already state issued placard. They are requiring their own review for approval. This is part of a reasonable accommodation request they required me to put in. For added context, the employee parking is in a separate fenced-off secure parking lot. They have their own ADA parking and assigned parking. This is completely separate from visitor parking.

I was under the impression that the state law supersedes the company policy. And that they can't deny me if I have all the legal requirements fulfilled.