Hillary won the nomination with a majority of the popular votes, and Trump did not. That makes me think that the Democratic primary was fair.
Joe, let's try your logic on a couple of other events:
The New-England Patriots won the Super Bowl by a wide margin, so deflating the ball was fair.
If all the votes in Florida had been counted, Bush would have won, so it doesn't matter how the Supreme Court reached its 5-4 decision in Bush v. Gore.
The e-mails demonstrate that the DNC did not conduct a fair race. Those who contributed to the DNC were defrauded, because the DNC had a contractual obligation to be impartial. There is no way to know if Hillary Clinton would have won an honestly run race, but I think one thing is clear. The former chairman of the DNC, Debbie W. Schultz had only 6 debates, which were scheduled on weekends or at the same time as major sporting events. This deprived Sanders of the exposure he needed, but it also left a lot of dead air time, which the Republicans filled with debate upon debate and which Donald Trump artfully used for free publicity. DWS may or may not have got the nomination for HRC, but at least she gets part credit (or blame) for Trump's nomination, and possibly for his election.