Can users remove themselves from my page of contributors?

Seeing there have been multiple similar questions in the past confusing contributors and collaborators, just stating this briefly so nobody ends up answering the wrong question:

  • Collaborator: someone with special privileges in a repository, these are easy to remove.
  • Contributor: anyone that has a single commit in the repository, shows up in the contributor list on non-forked repositories. This happens even if they never actually pushed or made a pull-request to my repository. I have confirmed this happens by testing.

My problem
I maintain a fairly complex organization on github forking and submoduling multiple different projects from people completely unrelated to us. For various reasons we can no longer maintain our project with submodules, meaning we’re going to merge commit histories into our main repository for any projects we no longer actively merge updates from. Whether this is a good idea or if we should be using subtrees is a different question, so I won’t elaborate on our situation further.

For contributors of projects completely unrelated to us, this means they will show up in our list of contributors on our main page, with no indication that their commit histories were just merged by us. For us, this would not be an issue on its own, we would gladly attribute them for their work despite not being for us, but that doesn’t mean said contributors would wish to be associated with us, and the way github presents this information really makes it seem like they would have been directly involved in our development for anyone not familiar with how git works. I assume this is why the contributor page is hidden in forks.

As we are not able to contact every person we would end up merging, this leaves us in a pinch. I would neither want to squash them out of their own commit history against their wishes nor plaster their face on our page without being able to ask them first.

Is there any way out of this dilemma?