It depends on the particular circumstances of both the published content itself and the organization responsible for stewarding the DOI.
Our membership terms require a good faith effort to plan for such a situation, and arrange to have any content they register with us archived by a third party.
Archives. The Member shall use best efforts to contract with a third-party archive or other content host (an “Archive”) (a list of which can be found here) for such Archive to preserve the Member’s Content and, in the event that the Member ceases to host the Member’s Content, to make such Content available for persistent linking. The Member hereby authorizes Crossref, solely in the event an Archive becomes the primary location of the Member’s Content, to contract directly with such Archive for the purpose of ensuring the persistence of links to such Content. The Member agrees that, in the event that the Content permanently ceases to be maintained by the Member, Crossref is entitled to redirect Identifiers to an Archive or a “Defunct DOI” page hosted by Crossref.
This is not always possible, unfortunately, and best efforts sometimes aren’t enough.
There are a lot of possible variables in a situation of an abandoned DOI that needs to be updated. Does the publisher still exist? Is the journal (or other publication) still operating, and under which publisher’s ownership? Is the publisher still a member of Crossref? Is the content available anywhere online? etc. etc.
As a general rule, when we’re alerted to this kind of situation, we do our best to find somewhere to resolve the DOIs too. If the publisher is still operating and still a Crossref member, we ask them to make that decision and do the updates. If not, then we will try to update them, for example, to resolve to a generic journal page, if the articles are no longer available.
10.5623/geomat-2010-0020 is a slightly different problem, because that DOI was never registered in the first place. So, it’s not just a matter of updating the resolution URL.
The publisher, Canadian Institute of Geomatics, is no longer a Crossref member. Their account was closed in March 2019. So, in order to register that DOI, or any others that they assigned and neglected to register, they would need to apply for membership again.
We can take it upon ourselves to update the resolution URL for a DOI registered by a former member. But, we can’t register DOIs directly, even if it’s obvious that they were intended to be registered.
Complicating the issue even more is that the journal Geomatica was transferred from Canadian Institute of Geomatics (10.5623) to Canadian Science Publishing (10.1139) in 2018. Canadian Science Publishing doesn’t have system permissions to register DOIs with Canadian Institute of Geomatics’ 10.5623 prefix. But if they supply us with the xml metadata deposits to register any DOIs that Canadian Institute of Geomatics neglected to register prior to the title transfer, we can submit them from an internal account. That’s the most likely method with which your article’s DOI will be registered and maintained.
Is the publisher that you’ve been in contact with Canadian Science Publishing? If so, we’re happy to help them with this process. If you would forward the email exchange you had with them to firstname.lastname@example.org and CC your contact there, that would be a good start.