Am also having this issue. Was building fine tell I upgraded codeworks to be able to do 28 as per google requirements. Now am being directed to this page. Did you find a fix?
You do not have to upgrade codeworks to do API level 28. You need CodeWorks 1R7u1 in order to reduce the numerous issues with this engine by more than half.
Open codeworks and have it completely uninstall everything, possibly except your android SDKs.
Run android.bat or install android studio and use that to only install the other SDKs you need, like API 28
If you plan on supporting Android 6 or below, in your project settings in the SDKConfig section set NDK API Level to android-19 and the SDK API Level to latest