Not sure what’s missing.
Since the missing symbols are related to GameKit, I’d start looking there.
Checking the extension manifest of extension-gamekit, it doesn’t seem to support x86_64-ios. Perhaps you can make a pull request to update that extension?
Note to future users: When posting the list of dependencies, we prefer it if you post it as text. Both for searchability, but also it’s a lot easier for us to copy paste into an empty project, to look for issues or to try to reproduce the issue.