Discrete Job DFF with EAM

We've been running discrete manufacturing for years and have a DFF set up with an automatic reference field of "M_JOB_TYPE". At this point, we are trying to implement EAM which also uses work orders, but the form is completely different - different block names, different field names. JOB_TYPE doesn't exist at all on the EAM form. I even tried using "CLASS_CODE" which is on the EAM form, but this gets converted to W_JOBS.M_CLASS_CODE - and since W_JOBS isn't a block on the EAM form, it fails.

We found this article indicating that global variables could be used: How to Avoid The APP-FND-00676 For DFF's using Reference Fields From Different Forms