Regarding OP's query: I concur with observations that this is not likely to lead to issues in returning to Canada as a visitor (or applying for other status, such as work permit or another PR visa). I concur, in particular, that if the departure was verified by a CBSA officer at the PoE that it is near certain it will not cause any problems.
However, I am not sure of the mechanics. Worst case scenario is a former PR might need to obtain Authorization to Return to Canada (ARC), which would become apparent when they apply for eTA or a visa. In the case of a former PR, this should be little more than a formality. The person affected, such as the OP, would be prudent to keep a clear record of the date of departure and good copies of tickets and such documenting the departure; with such documents there should be no problem at all obtaining the ARC.
An ARC should only be required if the former PR is the subject of a Deportation Order. According to some sources, technically the Removal Order will automatically become a Deportation Order
sixty days after it is issued but
*only if the former PR does not leave Canada before then*, that is, does not leave within sixty days after the Removal Order is issued.
It is sixty days because the Removal Order itself does not take effect, is not enforceable, for 30 days after it is issued (and not then if an appeal is filed), and a person has 30 days to leave Canada after the Removal Order becomes effective. So a total of sixty days.
It is worth noting that while the ARC comes up regularly in other contexts, so far as I have seen that is overwhelmingly in regards to FNs issued Removal Orders, not former PRs issued a Removal Order having lost status due to a RO breach. No guarantee that former PRs have not had to obtain a ARC to travel to Canada, but it suggests it is either not common or so easily resolved it does not come up as an issue.
. . . ask Agency A for info about yourself under ATIP and I believe they will only provide you information that they 'own' - even if they know about or can access other info at Agencies B-Z, they may not be allowed to share that info with you.
Fully agree with the good explanation in that post.
In ADDITION, even within an agency's databases and otherwise stored information, the ATIP only generates a copy of the individual's personal information, that is, information specifically stored in relation to the individual. An agency or department could have (very commonly will have I'd guess) a great deal of information related to particular individuals that can be accessed or retrieved but which is not stored as "personal information" and thus will not populate the ATIP output.
I am not sure I can clearly explain how this works, what it means. And it gets complicated. I'll try (a few years ago, as recounted here by me in numerous posts, I researched the nature and scope of PIBs related to immigration, but it's a huge subject, complicated, lots of nuances, and the weeds are deep and thick and expansive, and I have not revisited that much in depth for at least several years now).
The information that is generated in response to the ATIP is that maintained in PIBs (Personal Information Banks). That is not all information the agency has about an individual. (And, as
@armoured explained well, the information obtained by ATIP is information within that agency or department's control, thus in a PIB in the agency's control, and does not reach information in another agency's PIBs even if though the agency can access it; note, for example, IRCC now has more or less direct access to CBSA travel history, but an ATIP request to IRCC for the CBSA travel history will not work.)
For purposes of the discussion here, the key element in this definition is that the information is
*organized* by identification of the person. It will also be retrievable by identification of the person, but other databases and collections of information can be subject to search functions which will facilitate recovery (retrieval) of information about individuals within that information, without it being organized by the individual person's identity.
CBSA, for example, maintains personal travel history information for all individuals entering Canada. While there is no assumption every entry into Canada is captured in these records, as to the individual, for many years these records have been both complete and accurate for almost all travelers. These are available to the affected person by ATIP.
Note: most exceptions, though not all, where an entry record is not captured, are due to a technical failure to capture the entry or a deliberate skirting of record-capture by individual travelers. The latter ranges from travelers using alternative travel documents to unregulated entries. The unregulated entries are more common than many want to acknowledge. Roxam Road, in the news a lot of late, is hardly unusual let alone an anomaly, noting though its popularity and notoriety has made that particular location less suitable for those trying to enter Canada without being subject to border control, noting that those crossing there these days are arrested, making it perfect for those who want to seek refugee status from within Canada (while arrested, they are soon released into Canada and, for now, can pursue their refugee claim from within Canada).
So that travel history of entries into Canada, maintained by CBSA, is readily obtained by an individual through the ATIP procedure.
Exit data comes from multiple sources. It is not clear to what extent CBSA integrates such data into its PIBs for individual travelers. I do not know, for example, what CBSA does with the data it gets from the U.S. regarding travelers entering that country from Canada, effectively documenting the traveler's exit from Canada. I do know that CBSA can fairly easily access that data and identify a particular traveler's history of entries into the U.S. (thus exits from Canada). But unless CBSA actually organizes the information in that data according to the identity of the individual traveler, it will remain outside the scope of the ATIP request for personal information. Similarly flight manifest information acquired by other agencies and shared with CBSA. CBSA might very well take control and maintain its own database of this information, but it only becomes accessible to the individual if it is also organized by personal-identity.
The difference is what is readily populated in a database query versus what can be retrieved from databases through search functionality.
Whether that is a legitimate distinction that should be allowed under current privacy and access to information law, or as some might argue a loophole agencies use to minimize what they have to share with individuals, is not for me to say. All I know is that even good governments will tend to hide as much as . . . well, as much as they can get away with hiding.
