That’s what I think. I personally think his parents did just waltz across the border, no paperwork done at the time of his birth and his only citizenship was Canadian. Maybe not but it looks more like that every day.
It certainly appears to be the case. Frankly, based on what’s known about his parents, they don’t appear to have been very responsible people, but impulsive & selfish. The apple doesn’t fall far from the tree.
It's certain, otherwise he would have produced the paper...and if his parents didn't get the paper, he would have produced the formal petition to the US Government (and response) that certified his Citizenship.
While he may be entitled to Citizenship by Birth, he apparently has not completed the rigor to certify it.
One could make a case that his election to the Senate was fraudulent.