Earlier quoted context omitted.
Looks like an insect stuck on the camera lens.
There were multiple contacts and the F-18s had telemetry on the objects, it wasn't just an optical trick. Also how do two different jets see the same insect stuck on a lens?
About the radar comment: how often are there false positives on the radar? If they didn't see anything at all, would they have written off the radar results because they normally get that kind of noise? Maybe after thinking they saw something, they read too far into the radar noise.
Yeah, I know I'm proposing a couple coincidences, but we only hear about the situations where all the coincidences line up. And really, a couple mild coincidences lining up like this must happen often across the world, and seems more likely to describe this case than this being something extraordinary.