Yeah I understand your concern. If I am not mistaken the reason you cant see the backup is because it is in protected storage. I think cwm does this by design now... Have you tired booting into recovery and looking for it in cwm?Once you figure out where cwm saves it you can tell online nandroid to save it there, or you could just boot to recovery and do your nandroid directly from cwm. Personally I prefer to do it "online" so I don't have to reboot...
I really cant be of much more assistance directly becuase I don't have CWM on the device right now, but It looks to me like you pretty much have it licked. I'll check back after I get some sleep and If you are still having issues I'll flash cwm and see if I can be of any further assistance.