Recall all those rightwing hoaxes about voter fraud? Then the president appointed the vice resident and serial liar Kris Kobach to lead an inquiry into voter fraud.
Turns out that is fake, too. (See http://beta.latimes.com/nation/la-na-voter-fraud-commission-20171223-story.html#nt=oft12aH-1li3)
Kobach and Pence and WBD know the allegations of voter fraud were faked from the get-go. Kobach especially. So it make sense that they would not want a real inquiry. But you might guess that they could have maintained the sham a bit more carefully.