> guaranteeing the accuracy
The entire construct of "disinformation" is a strawman. There is ample historic evidence that the populations of societies subject to lying government organs (c.f Pravda in USSR) learn to discern deception.
If "disinformation" was so potent and deadly, none of the authoritarian societies that heavily relied on disinformation and lies would have needed to apply secret police tactics to control the population. They had both and they all still collapsed.
"We need to control disinformation" is double speak for "we control what you are permitted to know".
Propaganda is not a recent phenomena and we went through an entire Cold War with a noted power with excellent propaganda techniques (soviets) without censoring at this level.
The red scares and blacklistings and HUAC were just my imaginings.
Just one will do.
If your asking if a news group has ever refused to run a story due to dubious sources, yes. That happens all the time and has happened as long as there has been journalism.
Likewise, if we want to talk about social norms -- private publishers have long enjoyed editorial authority in the US. Only in very few specific instances have we forced private publishers to publish against their will.