I don't have much experience with distributing paid applications through Managed Play but according to this documentation from Google it sounds like it may no longer be an option?

 

https://support.google.com/googleplay/work/answer/6150398?hl=en

 

"Managed Google Play no longer supports the ability to purchase app licenses. Your organization can still manage and request refunds for the app licenses it already owns. However, it won't be possible to purchase any additional licenses."