When running with CIMSession the credentials are not passed to the PSSession which is used to copy the modules. The line below doesn't get the credentials so it attempts using the current users credential. https://github.com/Microsoft/DSCEA/blob/92401ff974b7934448aa9abd392064ec44043f65/functions/Start-DSCEAscan.ps1#L178
When running with CIMSession the credentials are not passed to the PSSession which is used to copy the modules.
The line below doesn't get the credentials so it attempts using the current users credential.
https://github.com/Microsoft/DSCEA/blob/92401ff974b7934448aa9abd392064ec44043f65/functions/Start-DSCEAscan.ps1#L178