If they insisted to be served in French then they would have to be served in French, but what little of the situation has been detailed this does not seem to be the case.
It's a little shocking that you're under this impression. The Charter of the French Language in Quebec ensures the right of consumers to be informed and served in French. It does not prevent people from serving you in English or any other language for that matter.
They have a Rust game: https://medium.com/embarkstudios/embarks-creative-playground...
Which maybe be using their PhysX bindings but it's not The Finals