flutter: PlatformException(sign_in_failed, org.openid.appauth.oauth_token, invalid_audience: Audience is not a valid client ID., null)

I am trying to add google sign in (without firebase) to my flutter app.

I have created google cloud project, created oauth consent screen and credentials. I am using

  google_sign_in: ^5.3.2
  googleapis: ^9.0.0

Also i had to add

 <dict>
    <key>CFBundleTypeRole</key>
    <string>Editor</string>
    <key>CFBundleURLSchemes</key>
    <array>
        <string>com.googleusercontent.apps.618518636914-abc</string>
    </array>
</dict>

to allow ios to launch browser for google sign in, I am able to enter email and password, after that the app permission screen (This app wants to access your google drive... ) screen briefly appears and disappears, and i can see this error in terminal

   [VERBOSE-2:ui_dart_state.cc(209)] Unhandled Exception: PlatformException(sign_in_failed, org.openid.appauth.oauth_token, invalid_audience: Audience is not a valid client ID., null)
#0      StandardMethodCodec.decodeEnvelope (package:flutter/src/services/message_codecs.dart:607:7)
#1      MethodChannel._invokeMethod (package:flutter/src/services/platform_channel.dart:177:18)
<asynchronous suspension>
#2      MethodChannel.invokeMapMethod (package:flutter/src/services/platform_channel.dart:377:43)
<asynchronous suspension>
#3      GoogleSignIn._callMethod (package:google_sign_in/google_sign_in.dart:247:30)
<asynchronous suspension>
#4      GoogleSignIn.signIn.isCanceled (package:google_sign_in/google_sign_in.dart:377:5)
<asynchronous suspension>

This is the code used for login

class GoogleSignInApi {
  static final _googleSignIn = GoogleSignIn(
      hostedDomain: "",
      clientId:
          "618518636914-abd.apps.googleusercontent.com");

  static Future<GoogleSignInAccount?> login() => _googleSignIn.signIn();
}

i referred this post Google Api and android Oauth INVALID_AUDIENCE error, but my client id is correct and it's of type iOS client only (in google oauth credentials) and Google Sign in fails on iOS 13 GM this is for pure iOS project, it might be still relevant. But i am not able to figure out the version of iOS's AppAuth which is used by flutter's google_sign_in.

Any help will be highly appreciated, thank you.