In the worst case you can create a "Stub EDS" just to allow RSLinx Classic to identify the device. Because you're very likely not using RSNetworx for EtherNet/IP to configure the GE drive, you don't need any of the Parameter Object or Bridge keywords in the EDS file.
Is RSLinx Classic browsing the GE drive and showing it as "Unknown Device" ?
If it were my system, I'd use the ControlLogix to send a "List Identity" service request to the GE drive, and use those values for Vendor, Type, Device, and Revision to create a Stub EDS using the EZ-EDS tool from the ODVA.