Okay so two questions.
1 - How'd you decide that this game's using your microphone? Any proof, pictures, saved recordings, that kinda stuff?

2 - For what reason would a mobile game with minimal controls need access to our microphones? Heck, if you can prove this game is doing that, it needs a serious investigation.

Here is some evidence

https://imgur.com/a/UsvnBKA

I don't speak french, but from that I can guess at whats going on here. I'm also on Windows 10, and my screen looks different to yours. Could be a Windows 11 driver update that installed a new version of the GFE for you. Do you use the GeForce Experience Instant Replay? You might know it as ShadowPlay. There are reports of things as innocuous as Paint Net using the microphone when in fact its a "feature" of Nvidia's. Apparently it comes from the GFE wanting to record all your desktop apps for playback.

Of course that's only one option. I personally do not have this game showing on that microphone activity list. I'm also nothing to do with this game, so I can't rule out that it could actually be doing something in the background. Still not sure why it would, but again that would need an actual investigation. Shady developers do exist, I'm just hoping this isn't the case.

I've played for over 4h today, multiple different sessions, I don't have the game listed in my microphone privacy bit. Nor camera or anything else like that. It's most likely you had an overlay capturing something and because it was hooked into the process, windows only saw the game's process and not whatever overlay it was.