I had a similar problem with a backup on my Nexus 5. It was working in realtime, but nothing was restored. I tried it several times, sometimes it took 30 minutes, sometimes it took just some seconds like your Nexus 10. I had to install the apps first and then it restored the app-data for those apps.
Try to install an app and restore its data, maybe it is restored. Try it more than once! If it's not working, try to encrypt the backup and restore it manually, there are many tools which work more or less, you can find it all on XDA!
I installed Candy Crush Saga on my resettet device and it was on Level 1. Then i restored and i was on level 347. So i found out that restoring just works if the app is installed.
I hope this works for you too.