Now the circumstances are on the other foot, and I will guess that Cruz will get the same treatment and be eligible for the Presidency.
There are four people in the U.S. who can demonstrate perfect Article III standing due to their alleged particularized injury: John McCain, Sarah Palin, Mitt Romney and Paul Ryan, the only other people to receive Electoral votes under the 12th Amendment and to therefore have a chance to become President by winning a majority of Electoral votes.
None of those four filed suit.