This patch requires the OMS Patcher 13.9.4.1.0:
"Ensure that you have the latest version of OMSPatcher version 13.9.4.1.0 for Enterprise Manager 13.4.0.0.0 release."
When you go into the note 2646080.1 it states the obvious:
Download Patch 19999993 for EM 13.4.0.0.0 from My Oracle Support. Make sure the description of the patch reads version 13.9.4.1.0.
That's not really what happens:
But when you download it anyways, it is the correct one!
I opened a ticket with Oracle Support to get this correct, in the meantime, use the same zip file for the earlier version.