Thank you for taking the time to analyze the game and for the suggestion!
Maybe I should consider adding a timer for when you complete the rats event.
Anyway I am thinking about reworking the mechanic complitely since I would like to make it to be more cohesive with the main gameplay loop as somebody else told me in the comments!
For the exploit, at first I didn't notice you could play like that, but thinking about it made me realize that if a player sticks to the "correct" way of playing the game they will end up making more points compared to the player that tries to cheese the game, so I believe it is not a major issue as of right now.
This said I am glad that you enjoyed our game, have a good day <3