Do you think aliens in ufos have visited Earth? (And all things UFO)

It's either true, or he is lying. He gave congress a list of names of individuals to get further testimony from about all the various programs. That's a weird move if he is lying.

Also, people are going to make up their own line of demarcation on when the UFO's are real. If yours is a green man comes out of saucer and shakes your hand. That's fine. It's all completely legit to consider this "real" when a government employee who has confirmed been involved in the programs, gives testimony, and additional witnesses to verify his own testimony.
He left himself an out, so that doesn't necessarily mean he's lying. I get why you'd think he's lying, but he was clever enough to not get himself boxed in. He's no dummy.