I don't think the premise is too outlandish, as long as the story unfolds to reveal some sort of high-level conspiracy (which I think it does/will). The suggestion that Stern and even the judge might be in on it is interesting.

What doesn't work great for me is the characters' reactions to the closing. I'd expect anger, confusion, disbelief; but there seems to be a lot of depression and nonchalance and "guess I'll have to find a new job." Rather than having a bunch of employees just wander away, it might be interesting to have someone decide that Perry must have been planning this for months, and lead a cavalry off to do their own investigation. I'd expect especially a lot of the non-reporter staff-people to follow.

Interesting little mystery, though!

The idea behind some people leaving was that the Daily Planet would probably mean more to some people than others. (Skip never thought it was an impotant enough job, for example.)

As for the amount of people who are actively particapating in the investigation, I went by the people who particapated in the "What happened with the Daily Planet" in House of Luthor. Even though they were all upset, only Perry, Jimmy, Jack and Clark investigated it.

I figured there would be a level. Those who don't care at all because it was "just a job."
Those who care but are more concerned about money for various reasons so they have to look for another job, and those who will stick by the Planet no matter what because it's "like family."