He's made no pretense that he's actually directly observed or been in contact with NHI tech, but yes he is claiming these things exist based on his role as an intelligence officer tasks with investigating the issue. He is also making specific allegations about illegal misappropriation and administrative retaliation through both quasi-legal and extralegal means. Claims which, again, have been judged "urgent and credible" by the inspector general of the intelligence community.

Again, you can forget aliens (for now). The story isn't about that, at least not yet. It's about the potential existence of rogue elements within the Defence/IC operating under the cover of secrecy to conceal what *they believe* to be technology of incredible importance and power.