No, they were incorrect.
While Canada might've had him listed as a citizen, because he was born there, he had not taken the steps necessary to claim that citizenship upon reaching his majority. Consequently, Cruz was an American citizen. Period. It made no difference what errant Canadian records might say.
The DMN's flawed report required that Cruz formally renounce his Canadian citizenship eligibility -- but it wasn't really necessary.
You are entirely mistaken. Cruz own spokesperson confirms that Ted was a full on Canadian citizen:
‘Spokeswoman Catherine Frazier said the Tea Party favorite formally gave up his citizenship May 14. He received official confirmation of the action at his Houston home Tuesday.’
snip
‘News that he had renounced his citizenship was first reported by the Dallas Morning News. The newspaper also broke that Cruz had dual Canadian-U.S. citizenship when he released his birth certificate in August.
Frazier said Cruz “is pleased to have the process finalized” and that it “makes sense he should be only an American citizen.”’
http://www.foxnews.com/politics/2014/06/10/ted-cruz-renounces-canadian-citizenship.html