you have to go into your settings for your org and click the arrow next to his name. then goto manage aps and there you can assign apps that he can see. if you only want him as a developer and not able to view financial stuff etc id change his role in the menu below also.
also for him to download the game you need to goto your build channels and add his email there so when he tests the oculus entitlement will work. adding him to a beta channel will send him a link that allows him access to the game downloads etc.
You can also assign what build that you have uploaded to the channel you wish for staff to use by clicking this: then changing the drop down to your latest build ETC This will require you uploading your build 1 time, then you can change that build to be in any channel you want. once you upload new updates the RC channel should auto change to the new build if you upload to the RC channel but will NOT change the other channels. you must change what build shows for each channel manually NOT UPLOADING IT Just changing the build in the drop down. this way alpha can be version 1.1 and RC can be 2.2 and staff channel can be 4.9 or whatnot.
Hope this helps... if you need any more help just flag myname with the @ flag and when i have time ill send you a message back.