I agree. This could be nothing more than problems with a certification of conformance or something similar.
As usual, the sensationalism of the subject implies airworthiness and/or safety problems yet we know no facts. I would strongly suspect the motives of these three employees (considering the hundreds or thousands that may be familiar with the issue). What exactly drove them to this revelation? That is a key part of this story yet to be told.
By the way. These three worked at one of the plants that Boeing is trying to sell to Onex. They might of lost their jobs in the deal.