Patch 14001330:R12.FA.B 12.1.3 fails with 'FAILED: file XLIFFLoader.class' errors

DBA attempted to apply patch 14001330:R12.FA.B in test instance and it failed with:-------------------------------------------------------------------------------
ATTENTION: All workers either have failed or are waiting:

           FAILED: file XLIFFLoader.class on worker  1.
           FAILED: file XLIFFLoader.class on worker  3.
           FAILED: file XLIFFLoader.class on worker  4.

ATTENTION: Please fix the above failed worker(s) so the manager can continue.
----------------------------------------------------------------------------------
We don't find any notes on this, so we need to know how to resolve this so we can apply the patch successfully.