android manifest vungle unresolved class

Question

in my app I am trying to implement IronSource adds. All of its networks are working except for Vungle. I followed the steps provided here by the official ironsource page however in my Android Manifest I get the unresolved class error for both my vungle activities.

Bellow is my android manifest with just the part that isnt working, the rest has been ommitted because it works. As mentioned, the two vungle activies (VideoFullScreenAdActivity and MraidFullScreenAdActivitiy) are giving me the error unresolved class.

In my app Gradle file I have the required maven link and the vungle jar as well as the dagger-2.7jar and javax.inject-1jar in my lib folder as instructed in the above link.

I have no idea how to resolve this error, any help is greatly appreciated. Thanks.

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:installLocation="preferExternal"
    package="com.Company.ProductName"
    android:versionName="1.0"
    android:versionCode="1">

    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" android:maxSdkVersion="18"/>
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

    <application>

        <!-- IronSource -->
        <activity android:name = "com.ironsource.sdk.controller.ControllerActivity"
        android:configChanges="orientation|screenSize"
        android:hardwareAccelerated="true"/>
        <activity android:name = "com.ironsource.sdk.controller.InterstitialActivity"
        android:configChanges="orientation|screenSize"
        android:hardwareAccelerated="true"
        android:theme="@android:style/Theme.Translucent"/>
        <activity android:name="com.ironsource.sdk.controller.OpenUrlActivity"
        android:configChanges="orientation|screenSize"
        android:hardwareAccelerated="true"
        android:theme="@android:style/Theme.Translucent" />

        <!-- Vungle -->
        <activity android:name="com.vungle.publisher.VideoFullScreenAdActivity"
            android:configChanges="keyboardHidden|orientation|screenSize|screenLayout|smallestScreenSize"
            android:theme="@android:style/Theme.NoTitleBar.Fullscreen"/>
        <activity android:name="com.vungle.publisher.MraidFullScreenAdActivity"
            android:configChanges="keyboardHidden|orientation|screenSize|screenLayout|smallestScreenSize"
            android:theme="@android:style/Theme.Translucent.NoTitleBar.Fullscreen"/>

    </application>
</manifest>