Yes, an election date is a fact. Claiming something else easily constitutes voter suppression. I don't know what laws the US has around this but I imagine a court could easily criminally punish entities for doing this.
However - especially when it comes to covid, you really are in gray areas. And even the authority makes mistakes, how do you then "fact check it"? When the WHO claims in january its not airborne, or Fauci says don't wear masks one month, and wear them a month later? When the WHO says lock down your countries, and just this week says actually you shouldn't? Hydroxychloroquine was used in many countries, by medical doctors. Just because trump said he is taking it doesn't make it a conspiracy theory. At the time there were legitimate doctors trying legitimate theories. Even if it turned out to be false, it's ridiculous to claim this issue is black and white.