The fact that you are in canada does not change who is responsible for I-140: CIS.
As to dual intent, I'll repeat what I've said to you before: CBP is under direction NOT to deny TN (for dual intent) solely on the basis of pending or approved I-140.
http://www.trowlaw.com/pdf/mar-09.pdfQuoting the Morris letter of 4/21//08:
"the mere filing or approval of an immigrant petition
[I-140 is an immigrant petition - agn] does not automatically constitute intent on the part of the beneficiary to abandon his or her foreign residence."
If you show up with evidence that you have even attepted to withdraw an I-140, then there is even LESS likelihood of denial.