I'm wondering if the problem is the nesting of projects. We have Projects and the Parent Code can be found in the Project Group data. We have Parent Codes for some of those project groups, which are also project groups. i don't think you can have a Parent Code that refers to another item in the Project data.
(We are still using PFP, so it's possible IIP is different)
#ApptioPlanning(ITP/ITFMF)