Hi Lucas,
You can refer to following blog. Only few points are relevant.. You can try resolve your issue by creating a new LUW using a custom function module HR_INFOTYPE_OPERATION. The source code for custom function module is in the blog.
http://scn.sap.com/community/abap/blog/2015/01/22/sap-hr-synchronous-employee-data-update
Let me know the results.
Regards
Sandy