Non-mergeable green pipeline?

In the project I’m working on I have different pipelines (short pipelines) depending on some configurations (the first stage of the pipeline creates the configuration for the next stages). These short pipelines are missing some crucial stages and the users should not be able to merge them.

I would like to have a green pipeline but not being able to merge it. I mean, the users are triggering these short pipelines and then creating merge requests, but the merge requests should not be able to be merged only with a green small pipeline, but with a full one.

Right now, I have added a failing job at the end of the pipeline (to prevent the merge), but it does not look OK.

Is there another way to do this?