Mr Light wrote:
The Jaridian probe appeared in the sixth episode of the series, so clearly they planning on some kind of alien menace that early...
No, an alien
probe appeared in the sixth episode. It was later retroactively explained as being the work of the "Jaridians." But I do not believe the Jaridians represent Okie's original intent for those aliens. They're far too ordinary, just your stock sci-fi humanoid alien baddies.
It was clear the probe wasn't Taelon. The episode strongly implied it wasn't from a Taelon ally, either. Beyond that, yeah, it's ambiguous.