Applied at Nvidia for Unknown

I recently faced a setback with my application at Nvidia. After completing six rounds of interviews, both virtual and in-person, I received a rejection due to not disclosing my current employment status. I was impacted by layoffs at Microsoft in the last week of August, and I didn't think to mention my employment status since no one explicitly asked. I provided all necessary documents, including my offer and salary details, but it seems this lack of disclosure was a dealbreaker for them. I've already communicated that my omission wasn't intentional, but Nvidia's HR is standing firm on their decision. Now I'm seeking urgent guidance on how to navigate this situation and what my next steps should be. I'm feeling quite lost and frustrated.