I had the same issue where the wireless didn't connect before logon. I used these steps to login a domain user on a wireless only device.
Connect to your corporate wireless connection using the local account, then join the Windows 8 device to your domain. Then, connect to it with Remote Desktop from another computer using the domain credentials you want cached on the device. After a successful login, you will be able to login on the device locally.
This works because it doesn't completely end the local account session, so the wireless stays connected while logging on with the domain account. Hope this helps!