Gitlab integration with Datadog

Hello Everyone,
I am new here , I am looking forward for some support from the forum.
I am trying to integrate Datadog with Gitlab. I followed this gitlab documentation and did group level configuration , in parallel as suggested by Datadog documentation we need to do agent configuration as well which is as below.

   gitlab.yaml: |-
        - gitlab
      init_config: {}
        - {"gitlab_url":"", "openmetrics_endpoint":""}
      - source: gitlab
        service: gitlab

We are us gitlab SaaS, and do not have access to underlying server, not sure the open metrics_endpoint is right or not and if it is then why gitlab is not scraping the metric to Datadog.
I also looked into this Document where it mention that gitlab makes internal service metric available at the /-/metrics endpoint.

Any help would be much appretiated.