I also have the same Issue here. We upgraded to Enterprise v10.9, somehow Apps in the App Launcher were refering to localmachine name in the URL, I fixed that by editing the System Properties in Portal Admin with {"WebContextURL":"https://domain url.com/webadoptor/"} which solved the URL Issue and Apps in the App Launcher were accessible via the webadopter on remote URL. However now I cant create Offline Areas from the Webmap Settings and Field Maps app but interestingly if I used the Android app I can create an Offline area for the individual device.
I believe we could be having a similar issue. Did you get a solution for your issue? If yes, How do I fix this?