Sideloading workarounds For WIndows 8.1 Bing edition

i am developing win 8 app and faced an issue on publication. Since the app is corporate i decided to use sideloading. Now tablets came and i found that they use Windows 8.1 Bing Edition, and unfortunately, they will not be domain joined. During testing, for sideloading, i used windows developer license, which has to be updated every 1 month. Now, the app is ready to go to production environment, but i can not resolve how to install it properly. I found that sideloading is not available for this OS and it made sad - Tablets are purchased (

I tried to use this workarounds https://www.vanstechelman.eu/windows-group-policy-encyclopedia/3f859886761478520ce64a298b95d215/allow-development-of-windows-store-apps-without-installing-a

http://www.ghacks.net/2012/08/17/how-to-add-non-store-apps-to-windows-8/

But looks like it does not work.

What do you suggest? Is there any way to sideload app on Windows 8.1 Bing Edition? Should i publish it on Windows Store? Is it possible to limit access to app in windows store? Should i convert Windows app to WPF?