“something on the lens.”
Nope. It moves in and out of the frame as the camera tracks it. Something on the lens stays in the same fixed spot all the time.
You’re absolutely correct.
And the Pentagon wouldn’t be issuing its can’t confirm or deny statement for snot on a camera lense.
It's usually a fungus and it could slide, like when you have dust sliding along the lens of your eye.
When the technicians recharged the nitrogen (or argon) used to keep moisture out of the lens in order to prevent fogging, they either didn't get all the moisture out or inadvertently added some in.
https://www.lifewire.com/camera-lens-fungus-493473