As a bit of backstory, this particular quest has been driving me crazy since it started cropping up. Today I'd had enough and dug into the game files looking for answers. It seems to me that if the imp gives you "rich get richer" as a condition, all you need to do is gather 3000 of each resource and it should complete. Except the reward script doesn't trigger. I tried spending all my resources and bringing them up to 3000 from 0, letting them drop back to cap from above. I tried syncing the resource counters by destroying all my mines and converting my starting four again at the same time. Tried both of the above again, with the counters synced. I might be wrong about what's happening here but you'd know better than I would what's supposed to happen.