Is this clear from the evidence or are these the allegations against them?
So, sort of a paper tiger.
Does the US Government (as represented by these prosecutors) have a good faith belief these individuals committed these crimes? Probably, though you might believe otherwise. I would say my trust is very high in that statement, despite everything else going on in politics right now. The government doesn't make indictments like this lightly, and the grand jury saw at least enough evidence to establish probable cause. At the same time, there is a saying about ham sandwiches and indictments.
Will we ever see the underlying evidence? I doubt we will.
Should we trust the US Government's representations in this case? Again, I would - but you may have priors to suggest you shouldn't.
[0] https://www.justice.gov/opa/press-release/file/1328521/downl...
The evidence is presented at the trial, not in the initial press release announcing there has been an indictment.
One would expect that there is clear evidence, or there wouldn't be an indictment. You can't win a court case without evidence.