Hi, @skullptr! And welcome to Heroic Labs Forum!
@juryxiong has written a very interesting blog post describing a similar use case to yours: Documentation for headless instance orchestration layer - #13 by juryxiong
It describes a use case using Godot Engine but the concepts there might help you achieve a more optimal solution to your requirements.
In the meantime, and as mentioned in that post, Heroic’s team is always improving the documentation and that use case (headless + Nakama) is on the backlog 
Cheers,
Caetano