Hi Michael,
Netconfig will use the same credentials as other aspects of RME and Common Services.
There a couple of possibilities where things are going wrong. It could be a timeout in the connection or your device doesn't support the protocols being used etc.
Can you check RME -> Administration -> Config Management -> Transport Settings
See if the settings for Archive Management (sync archive) are the same as netconfig (I'm presuming that RME can sync the configuration of the devices successfully).
If they are different, try setting them to the same protocol, or the same order of protocols.
For the timeout, you may want to try playing with the RME Device Attribute settings. To check this, go to RME -> Administration -> System Preferences -> RME Device Attribute and increasing the timeout settings there.
To find out more detailed information about the reason for the job failure, you can also check the job log.
This is normally located in CSCOpx/files/rme/jobs/NetConfigJob/.
Cheers,
Shane