Yeah, you've got options, as others have said. You can leave for an active, healthy FC. You can try to document the bot's actions and submit reports showing they are a bot. Next time SE takes action against the botters their account would be banned. Then the next person who logs on would get FC ownership.

But, you're saying you've been left in the cold when you left the game and didn't take action to make sure someone was staying to tend the shop, as it were. Take some responsibility. This happened in part because of your choices. So now you get to choose how to recover from it.