Global Catalog server placement and child domains

Hi.  We have 1 forest and 2 domains.  Our second/child domain is now down to 1 domain controller and is being kept around for legacy purposes only.  It basically does nothing 99.9% of its life.

My primary domain uses 3 servers servicing 330 users in total.  They only need to service the immediate LAN.  Lets call them WIN1, 2 & 3.  Here are their respective functions:

- DNS: WIN1, WIN2
- RID Master: WIN1
- PDC Emulator: WIN1
- Infrastructure Master: WIN3
- Domain Naming Master: WIN1
- Schema Master: WIN1

Global Catalog Servers:
WIN1, WIN2

So, WIN1 is both the PDC emulator and a Global Catalog server.  According to Microsoft, the PDC emulator should not also be a Catalog server.  Oops.  So my plan is to remove the Global Catalog from this server and add it to another one.

WIN2 is already one.  WIN3 is the Infrastructure Master, so it shouldn't be used.  That leaves me with my child domain controller:  CDC1.   It is a PDC emulator for its own domain.  But has zero work load.  Can it act as a global catalog server easily accessible and used by the primary domain?