Idea:
One addition or expansion to the proposal would be a type of video that was a
hybrid with two sections:
Section 1: would be exactly what you have now, a video shot and then edited by the character and presenting what they choose to present to the world by posting it
Section 2: what really happened from a non-character 3rd person point of view (traditional camera role played in any television show).
This second section could be habitually indicated by a shift in music, video quality, lighting style ... something you establish and try to stick with fairly reliably. I think fans will catch on quite naturally to the difference, and this may be less confusing for fans to keep straight (and new fans to understand) than the private channels concept.
The video 0130 "The Human Ransom" is an close example, except that in this video Section 2 was accomplished by pretending that Tachyon had planted a number of cameras all around the scene.
Section 2 *could* be justified by some narrative invention (such as impartial supernatural or alien observers), but that may not fit into the mythology. And I'm not sure that is necessary.
In this suggestion, Section 2 would give the audience the "superior view" that none of the characters would have - we might see things they did not even know were there. You would not be limited to the private channel communications, but you could include such a thing in a Section 2, so this is really a superset of the original proposal.
This proposal also opens up your creative possibilities to include things a character could never video, such as flying camera pans, dreams, memories, flash-backs, etc.
Example:
Section 1 - Bree posts a video like 0128 "Me For Daniel" (talking to the world, but addressing the Order/Lucy, saying she is prepared to trade herself for Daniel).
Section 2 - We see a side view of Jonas filming Bree, the end of her previous statement, then Jonas turns off his video camera, and we see Bree ask Jonas, "Well, how was that? Do you think they will buy it?" ... Then Bree picks up the phone, dials a number, and speaks into the receiver, "Tachyon, we are ready when you are."
( and then there is much rejoicing and anticipation by the fans
)
Another Example:
Section 1 - Bree posts a video like 0160 "Vegas Baby!" showing the characters enjoying Vegas, and then being chased (but we don't see by who).
Section 2 - We see an Order operative spotting the Scoobies and then giving chase, and then calling in to report, "They got away, but we think we know where they are staying..." or "The plan's working, we let them escape, but handed the message to Daniel."