I think the problem stems from your definition of amnesty and Cruz's. Cruz defines amnesty as granting a pathway to citizenship. He does not define amnesty as granting legal status, which is what he favors:
http://www.americanthinker.com/articles/2015/08/ted_cruz_vs_donald_trump_whos_stronger_on_immigration.html
Please also clarify how Mrs. Cruz is a definite leftist.
Here is a good video on the subject which I think does a good job in clarifying exactly what that means:
https://www.youtube.com/watch?v=v6nYjbCOiLA
Video makes ridiculous “friend of friend” assumptions and uses Goldman Sachs as the boogeyman for all that is wrong with immigration and banking in America. No where in the video are direct quotes from Heidi Cruz used.
Then the video goes right off the rails with the “Cruz is not a natural born citizen” argument. It also erroneously states the qualifications for running for President.
The article you posted clearly states that they are basing their disbelief in Cruz’s immigration credentials on an substantiated NYT quote. If you prefer to pick your candidates based on the reporting of the NY Slimes, please go right ahead.