The last time I tried to update the Proton apps using Obtainium by scrapping the Proton github pages, it was failing more often than not. Oftentimes Aurora Store would show me updates were available for the Proton apps while Obtainium wouldn't find anything even when checking manually. That was the case few months ago.
Since then I've ditched Obtainium for Accrescent + Aurora Stora. While it's possible getting updates through Aurora is less secure than by Obtainium, it has been much more hassle free for me.