Cruz's paperwork, at his natural birth in Canada, says he's naturally Canadian.
We note that Ted Cruz recently officially gave up his Canadian citizenship well after his kids were born.
So...by your calculations, you're saying that his kids are Natural Born Canadians, too?
The conditions of Sen Cruz’s birth says that he was born a citizen, has always been a citizen, has never been naturalized and does not need to be naturalized. Title 8 section 1401 subsection G
I don’t know about Canadian law with regards to his kids. To answer your question, one would have to look at Canadian law which has no impact on US law.