I have a question, I’m not going to argue. I honestly wish to know your answer:
What happens if Senator Cruz wins the nomination and then loses a NBC court challenge? (Is the answer different after the election). My understanding is that the party still won and we would still get a Republican president. Would it be the VP, or could the GOPe get its dream of president Yeb! Or something else altogether?
The nomination? That only determines the partys candidate.
If it was determined he could not be President for any reason after the election the the VP would be President.
The details depend on exactly when the revelation occurs.
After nomination-before-general: Party names a replacement, generally party leaders in a closed room meeting. New person's name is on the ballot, if there is enough time.
After the general, but before the electoral votes are transmitted to Congress: Party chooses a substitute, electors transmit ballots with substitute's name to Congress
After Congress chooses a president-elect, but before inauguration: Election goes to the House. I have no clue if the party can toss in a new name at this point, I think not. 20th amendment says VP-elect gets the post. 3 USC says what to do if neither qualifies
-- could the GOPe get its dream of president Yeb! --
Anything happening before electoral ballots are transmitted to Congress is an opening for Jeb. After the ballots are transmitted to Congress, the choices are, I think, limited to the names on the electoral ballots, and 3 USC.
Point of reference, if you are old enough, is Agnew resigns, Nixon names Ford, Nixon resigns, Ford is unelected president. After inauguration, that's how it goes.
I think GOPe planned all along to take Cruz out at the convention, and use his delegates for Jeb or Rubio or some other establishment hack. No court case needed, the GOP has the authority, on its own, to disqualify Cruz.