In my case i wasnt part of his application actually he kept alot of that private even the papers even though i was guiding him through it. He had a misrepresentation case already trying to get PR that was dropped when we hired a good lawyer. The CBSA officers thought he didnt submit claims about our sons birth but he did they didnt see it. so when they detained him they went through his phone found our messages and questioned him about the relationship. the case was dropped and was given a new interview by CBSA based on the fact he shouldnt have been detained in the first place he had submitted proper documents for our son. That part I dont know what he said as he refused me to come there with him to the new interview (red flag). Even though our relationship was part of the questioning. I assumed he told them the truth... but in 2016 the legal wife arrived (actually he didnt even tell me they came I found out through facebook) that was alarm right there but again his family and him convinced me otherwise. Im assuming now he told that CBSA officer he wasnt living with me. that we had a fling got pregnant and he was just helping out our child sometimes until the wife came. Im pretty sure now he lied to that officer. I feel so stupid.There was the time I was surprised as well that people were able to claim just to be separated from their previously married spouse (not even legally separated) and then they can take in different partner as his or her spouse for immigration purposes. In order for that to happen they should not live together with the previous one for certain period of time and then live with the new person for some time.
In this case he was at the same time living with the new person (not just a love affair, but really living together) and at the same time claiming relationship with his legal wife (his application for PR is a proof of that). so with that said he actually did commit a fraud at very least. (for what I know it might even be classified as a bigamy).
From what I understand at least 1 child is involved in this matter and it might still be nasty regardless if she pursue it or not (hello battle for right for the child). That is exactly the moment where she wants to show who that partner is and just how little that child has to gain from him. If he had not problem to lie her for years, what would stop him to use the child as a "hostage".