We haven’t included the full tweetstorm, because it would take up quite a bit of room. You can read it here. As for voter fraud, Hasen concedes that it does happen, however, the accounts by Trump are exaggerated.
Hasen explained more in an op-ed on TPM
Claims of voter fraud are often exaggerated by orders of magnitude. Consider the claims about non-citizen voting. Matt Drudge recently had a headline stating: “Report: 1,000+ Illegal Voters in Virginia.” And Dan Scavino, Jr. tweeted: “Terrible. We know who the 1,000+ illegal aliens ARE NOT VOTING FOR! A fixed presidential election in the making….will we ever know!?!?” But if you look at the underlying report, they have identified only 31 actual non-citizen voters in Virginia over the last 10 years. No doubt there are some more, as not all the counties have responded yet. But it is not 1,000 plus non-citizens voting in Va. (“In the 8 jurisdictions that provided us with lists of aliens recently removed from their voter rolls, we discovered that 31 non-citizens had cast a total of 186 votes between 2005 and 2015. The most alien votes were cast in 2012 followed by 2008, the year President Obama was elected to his first term.” (emphasis omitted)). Don’t believe all the hype. Non-citizen voting is a real, but pretty small, problem (because the penalties are high and the payoff low).