Why is the vid unlisted?
This ain't for the general public. It's for folks still in Scn. I'm guessing that they're realizing that Scn public and staff aren't staying off the 'net anymore, and that this is an attempt to "handle" that situation.
You're incorrect. OSA knows that anyone in the public arena that hears of, or reads about Marty Rathbun in various news articles, will Google search his name and find links to John Allender's blog where the video can be found, or be linked to the YouTube video that the public can access freely. If it was to be an eyes-only video, it would have been designated as private.
You have to remember that OSA does not always pull pranks in the open. Much of what they do is covert, and in the age of mass media & the Internet, they've learned to adapt & pull shit under the wire.. instead of mass marketing their stupid videos, they place them on individual's blogs, which leaves the public (ignorant of the crap Scientology/OSA plays & has played in the past) believing that the video is not a cult-driven attempt to slime Marty, but one of concerned citizens.
It also plays into the hands of "The YouTube Team". If Marty files a complaint that the video violates their TOS by defaming him, the cult can always claim it was not aired for public consumption, but was "unlisted" for a reason.
If this video was truly intended to be private, and for Scilon-eyes only, it would not have been made available on public blogs, nor would you have been able to access it directly on YT. Chalk it up to OSA's being clever..