Is there a way to authenticate a MongoDB user before connection in a C# WinForm?

Question

I'm playing with building a MongoDB Explorer in a Windows Form specific to our implementation and I'm looking for the C# equivalent of db.Auth(). I've found this here:

mongodb: check user/password with c# driver

It mentions the Authentication section of the MongoDB documentation, but little else and the question is 7 years old. Comments there mention Client.GetServer, but that's deprecated and gone. I can try to list databases or the like, but all that gets me is a TimeOut exception.

I built this out and it works, but seems a bit backwards:

    public bool Authenticate(string userName, string password)
    {
        bool auth = false;
        ProcessStartInfo si = new ProcessStartInfo(@"C:\yada\blah\mongo.exe")
        {
            Arguments = $" blah--authenticationDatabase admin -u {userName} -p {password}",
            RedirectStandardInput = true,
            RedirectStandardOutput = true,
            UseShellExecute = false,
            WindowStyle = ProcessWindowStyle.Hidden
        };
        Process process = new Process();

        process.StartInfo = si;
        process.Start();

        while (!process.StandardOutput.EndOfStream)
        {
            string output = process.StandardOutput.ReadLine();
            if (output.StartsWith("Implicit session"))
            {
                process.Kill();
                auth = true;
                break;
            }
        }

        return auth;
    }