Hi Richard,
Putting the fact that it's a Exadata appliance to one side for the moment.
1. Have you tried to manually run the R3load -testconnect as user gwqadm ?
2. As user gwqadm, could you please check that your environment variables are set correctly (upload output and post it here).
Even though it's a bit dated, did you have a look at the following guide as a starting basis:
http://www.oracle.com/us/products/database/sap-exadata-wp-409603.pdf
Let us know.
Cheers,
Amerjit