A key point in that article was that some or even three of these criteria could be found in high conflict cases of divorce and post divorce, and still not be parental alienation. (nationalassociationofparentalalienationspecialists.com)
This appears to be in response to conflicting case law in many provinces, which has caused uncertainty and encouraged court challenges. (slaw.ca)
In high conflict cases involving custody, access and child support evidence of communications between the parties is often front and centre if the matter goes to court. (hhlaw.ca)