It seems pretty remarkable that airlines are buying such a security sensitive piece of software from a one person shop. If you make it very far into selling any piece of SaaS software to most companies in corporate America, at the absolute minimum they're going to ask you for your SOC2 audit report.
SOC2 is pretty damn easy to get through with minimal findings as far as audits go, but there are definitely several criteria that would should generate some red flags in your report if the company is operated by a single person. And I would have assumed that if your writing software that integrates with TSA access systems, the requirements would be a whole lot more rigorous than SOC2.