https://www.apkmirror.com/apk/facebook-2/work/work-255-0-0-34-121-release/workplace-by-facebook-255-0-0-34-121-4-android-apk-download/
Just downloaded the Workplace from Meta 255.0.0.34.121 (arm-v7a) (360-480dpi) (Android 8.0+) APK from @APKMirror