Yes, you can still get the key for free!

To get it you have to:

1. First, login with Keychain to Dungeon Cities;
2. Then, join the official Discord server and share your hive username in the channel called "hive-usernames".

In a few minutes/hours @blackheart1 will drop the key in your inventory on Dungeon Cities and you will be able to play the game for free :)