After setting up Crashlytics for NDK, I cannot see line numbers or symbols

Question

Hello after installing crashlytics in my Android app I have been able to successfully detect crashes with stacktrace in Java. After setting up the NDK however, my stack traces on Crashlytics only say:

0 libc.so (Missing)

1 libart.so (Missing)

2 libnative-lib.so(Missing)

3 libc.so (Missing) and so on with no symbols....

I have been through: https://docs.fabric.io/android/crashlytics/ndk.html, https://fabric.io/downloads/gradle/ndk and have made sure to run ./gradlew crashlyticsUploadSymbolsRelease. Additionally I have the line Fabric.with(this, new Crashlytics(), new CrashlyticsNdk()); in my MainActivity.java file. Does anyone have an idea what I could be missing ?

buildscript {
    repositories {
        jcenter()
            maven { url 'https://maven.fabric.io/public' }
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:2.2.0'
        // The Fabric Gradle plugin uses an open ended version to react
        // quickly to Android tooling updates
        classpath 'io.fabric.tools:gradle:1.+'
    }
}

apply plugin: 'com.android.application'
apply plugin: 'io.fabric'

repositories {
    jcenter()
    maven { url 'https://maven.fabric.io/public' }
}

android {
    compileSdkVersion 26
    buildToolsVersion '27.0.3'

    defaultConfig {
        applicationId "com.example.crashapp"
        minSdkVersion 16
        targetSdkVersion 26
        externalNativeBuild {
            cmake {
                cppFlags "-std=c++14 -frtti -fexceptions"
            }
        }
    }
    buildTypes {
        release {
            minifyEnabled false
        }
    }
    externalNativeBuild {
        cmake {
            path "CMakeLists.txt"
        }
    }
}

crashlytics {
    enableNdk true
    androidNdkOut     'build/intermediates/cmake/debug/obj'
    androidNdkLibsOut 'build/intermediates/cmake/release/obj'
}

dependencies {
    implementation fileTree(dir: 'libs', include: ['*.jar'])
    implementation 'com.android.support:appcompat-v7:26.1.0'
    implementation 'com.android.support.constraint:constraint-layout:1.0.2'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'com.android.support.test:runner:1.0.2'
    androidTestImplementation 'com.android.support.test.espresso:espresso-core:3.0.2'

    implementation 'com.crashlytics.sdk.android:crashlytics:2.9.9'
    implementation 'com.crashlytics.sdk.android:crashlytics-ndk:2.0.5'
}