Custom connector support for authentication with client certificate to PKI protected data source?

Would it be possible to write a custom connector for Power BI Desktop that allowed connections to a REST API or other web.contents services that are PKI protected and require use of client certificates to authenticate?  This is completely out of my realm, so I could be completely missing something, but I don't see any option in the Authentication methods for custom connectors to use a client certificate for authentication to PKI protected data sources (like a REST API on a private network).  

Are there any examples of how you could get started building such a connector via Power Query?  I don't see an obvious option for authentication, but was hoping there was a workaround using one of the existing methods that has been leveraged by someone far more knowledgeable than myself...

This has been a complete showstopper for using a lot of corporate data sources, as I have no other authentication option.  Sadly it is trivial with many other products or through options like Python, etc... If anyone has examples or advice on how this can be achieved using Power Query (custom connector or not) it would be greatly appreciated.  Thank you