I'm having the same exact issue. I haven't been able to figure out how to fix it and searching for resolution hasn't been fruitful at all.
Edit: The docs mention this for 'installing' or 'updating' but I'm not sure it would work. It looks like it has more to do with 'agent' errors instead. https://github.com/lutris/docs/blob/master/Battle.Net.md#sleeping-agent--issues-with-installing--updating-