Oceania, at the end of the game, there’s a bug, can you help? Auto-translated

So, I spent a very long time playing the "Oceania" map (not WOG, just the regular Heroes of Might and Magic III: The Shadow of Death), and I finally defeated almost everyone. In the end, one computer-controlled player hid in a closed-off area in the upper right corner, and the only way to get there is by bringing the "Sphere of Permanence" artifact. I control the entire map, but this artifact is nowhere to be found. What should I do?

You can obtain the Sphere by completing a quest located on the small island below the underground world. For this, you need the Amulet of Clairvoyance (which can be found near the Crystal Dragons on the same island) and the Red Orb (which can be found behind the hydras on the same island). Alternatively, it's best to get there using the Fly spell or Dimension Door.

The flight spell is blocked on the map. To reach the hydras, you need to destroy the red dragons, but there are none anywhere! If it's not too much trouble, could you take a look at the save file? http://yadi.sk/d/9CUFig_cDZLsn

Checked the save file, and there are indeed no dragons (apparently, the computer acted first), and there's also no control magic. Some smart AI placed the Grail in a Castle. There's still a chance, but if the pink AI killed the dragons, it might also open the gates, but that's unlikely. I guess I'll have to replay it. Generally, the standard Oceania map is played with control magic enabled. Someone must have edited the map.