I don’t think they get it. If they steal the nomination from Trump, he will have enough of the popular vote to go independent and take this to SCOTUS before the election. Since he would already have the delegate count, if SCOTUS kicks it back, Trump could then just run as a write in candidate.
Just what do you think he could take to SCOTUS? Sore loser laws? Since that is the province of the states, I don't think he could get through all of the state courts in time. Remember that SCOTUS has already accepted all of the cases it will hear this year, or will have very soon, and the new term will not start until October.
He would always have the option of running a write in campaign. All that would do is insure that Hillary will win, but I have come to the sad conclusion that will be the outcome regardless. If Trump doesn't get the nomination, his supporters will stay home. If Trump does get the nomination, the supporters of the other candidates, whom the Trump supporters have insulted and demeaned, will stay home or go 3rd-party. Either way, the eventual nominee is crippled in the general election.
What if the RNC and the DNC get together and tell us peons they are not accepting 3rd Party candidates???