Sakurai Energy has been their pen name for several years now, as well as his circle name being Sakurai Dai Energy. So I think the rename would be more than fitting.
The only place I could find Koutamii in was their pixiv URL, but their display name is still 桜井エネルギー.
As far as I can tell, all the information in their wiki is current.
Also, an alias for the name change would be most excellent.