Just to put a neat bow on this one I wanted to add the conclusion.
After more digging with the developers, I learned that this nested mounting was not intended as a pass-through from NFS to NFS. Rather, it was a means to nesting the NFS shares of other servers into the directory structure that was in turn shared out via CIFS (Samba).
The devs would run old VBS scripts that would check out files from VSS and then load them onto the target build machines which was where the nested NFS shares were originated from.
This method is very similar to NFS Gateway Services that Windows 2003 Services for Unix provides but that solution has been de-supported by M$ on Windows 2008.
I ended up rebuilding the services on a Linux box to re-create the lost functionality from the original Solaris server that is scheduled for decommissioning.