So after taking a look at the source code and seeing the key is a local variable, I just added a send_message(server, key +”\n”) right before it asks what the key is. I entered that key right away and it said Congrats etc etc, but didn’t provide a second flag, just blank space. Back to flag one though, taking that encoded text and key and pasting into CyberChef to decode it returns something not even close to a flag. It seemed I was going doing something wrong, perhaps I was using the tool incorrectly. After feeling stumped and checking write ups, I saw that rather than print the key, people went straight to CyberChef and used the known THM{ to get the first 4 characters in the key. Well after following their exact process, the first 4 characters of the key I get match the first 4 of the key I printed. I put the partial key in the box as UTF-8, and put the encoded text into the input. The output gives me the same issue of something that definitely isn’t a flag.
Between that and it not even giving me a second flag despite the “Correct” dialogue, what am I doing wrong?