Step 1: It is known that MAX is a bystander.
Step 2: MAX’s clue states that EMILY is a bystander.
Step 3: According to EMILY’s clue, all people whose names are 5-letters long and end with “E” are bystanders. Therefore, STEVE and JULIE are both bystanders.
Step 4: From JULIE’s clue, we know BRANDON and GREGORY are bystanders because they are the only males with 7-letter names.
Step 5: From STEVE’s clue, we know that OLIVIA and THOMAS are bystanders because they have 6-letter names.
Step 6: MELANIE cannot be a victim because she does not have a 4-letter name (OLIVIA’s clue), and she is not the person whodunit based on BRANDON’s clue. Therefore, MELANIE must be a bystander.
Step 7: DEREK is not the victim because he does not have a 4-letter name, and he is not the person whodunit based on MELANIE’s clue. He must be a bystander.
Step 8: JOHN is not the person whodunit because of MELANIE’s clue. He cannot be the victim because, although he has a 4-letter name, he cannot be seen by MAX (who we know can see the victim). Therefore, JOHN must be a bystander.
Step 9: Both REBECCA and CHELSEA must be bystanders because their names are not 4-letters long (they cannot be the victim) and their names end in ‘A’ (neither is the person whodunit based on JOHN’s clue).
Step 10: Since the victim has a 4-letter name and the person whodunit has a 3-letter name, all people with names of other lengths (MEGAN, SCOTT, and KRISTEN) must be bystanders.
Step 11: Since KRISTEN’s clue says that the victim is not in her row, MARY cannot be the victim. She has a 4-letter name, so she cannot be the person whodunit. Therefore, MARY is a bystander.
Step 12: The person whodunit has a 3-letter name, and Scott can see the person whodunit. Scott cannot see ELI, so he is not the person whodunit. ELI is not a 4-letter name, so he cannot be the victim. ELI must be a bystander.
Step 13: ELI can see the person whodunit, which means AMY cannot be that person (Eli cannot see her). AMY is not a 4-letter name, so AMY must be a bystander by default.
Step 14: MAX can see the victim, but AMY cannot, so the victim cannot be in their column (ADAM, who therefore must be a bystander) or in their diagonal cross-paths (STEVE, who we already know is a bystander).
Step 15: The victim and the person whodunit are of opposite sexes (THOMAS’ clue), and GREGORY is adjacent to one non-bystander. TIM can only be paired with RUBY, but both are adjacent to GREGORY. Therefore, both are bystanders.
Step 16: The only 3-letter name left is JEN. In order for at least one non-bystander to border GREGORY, MATT must be the victim. MATT and JEN are of opposite sexes, which satisfies THOMAS’ clue. By default, ERIC is a bystander.