Use dnspy to read Assembly-CSharp -
tjctf{wh3rs_
Part 2 - Use AssetStudioGUI - VictorySound2.wav (1.wav is japanese)
Voice says: Flag part 2 is: "the_T5sp1n" or 0x7468655f54357370316e (Hex gives capitalised T)
Part 3: Strings level0 and grep for '}' (probably not intended lmao)