Is it known that you cannot capture it with Curse from non-Crystal distro event raids? The only den I have verified can come with Curse is the rare purple ROM den.
(Also this page still says it)
Can you clarify what this means? It is possible to catch a G-Max Copperajah out of the rom den with Curse as an egg move, and it should also be possible to transfer it onto G-Max Copperajah via the Nursery.