Integrating customer GitLabs with ours for Issue tracking

I’m managing a GitLab instance where all the projects for our environment get stored and is used as our ticketing system using GitLab Issues. I setup some customers in their own projects and wikis that they can access and then they submit issues to us as needed. There are some customers that want to use their own GitLab in their environment, which is fine, but they would still need to connect to my GitLab to create tickets.

Ideally, what I would like to do is have a single project for each customer in my GitLab and have the customers be able to open issues directly in there from their GitLab. Due to limitations in what I’m allowed to do in the environment right now, I cannot setup another instance to test such a setup, but from what I’ve seen, I guess the Custom Issue Tracker would be my best option.

My questions:

  1. Would I setup a Custom Issue Tracker in my GitLab to point to each customer project they use for issues? Would this allow me to modify issues and reflect changes back to their GitLab, similar to being in the same instance?

  2. Is there a better way to integrate multiple external customer GitLab instances into my GitLab so that I could essentially be the “parent” GitLab instance that would receive all issues?

We currently cannot implement a different ticketing system, though that could be a possibility in the distant future. I’m going to be looking into API usage to see what could be done there as well. If it turns out to be something that becomes too much of a nightmare to manage, then it would probably be dropped and we’ll have everyone access my instance directly to submit tickets.

Any recommendations are appreciated.