The Sudokutown Murders by Loric and Nordy

Simon has attempted this excellent (and challenging) puzzle.  You can watch the video at the link below.  Definitely worth studying the rules at some length first - because every one of them is important!!!

Play the puzzle here:

https://app.crackingthecryptic.com/sudoku/pnQb9mpJ6L 

Simon's solve: 

https://youtu.be/vGp5xgKG4Hc

Rules

Normal sudoku rules apply. Digits within a cage cannot repeat, and must sum to the small clue in the top left corner (if given). Cages are referred to as "crime scenes" in the following rules. WATCH OUT! A serial killer is on the loose and is leaving crime scenes and dead digits all over Sudokutown. Luckily, Sudokutown's #1 Detective is on the case, and a few brave citizens have stepped forward to provide eye-witness accounts. But will the killer be caught in time? One of the digits is a serial killer. All instances of the serial killer digit appear on a single, 1-cell wide orthogonally connected path (Snake). The serial killer's path starts in the largest crime scene (44 Killer Cage, total of 8 cells), then moves to the next largest crime scene (7 cells), then the next largest crime scene (6 cells), and so on. Exactly two adjacent cells on the serial killer's path appear in each crime scene, with one cell containing the serial killer and the other cell containing a "dead" digit. Once a digit is "dead," that digit cannot appear in any future crime scenes. After the final digit is "dead," the serial killer escapes off the edge of the grid. Additionally, the serial killer appears on both ends of the path. The serial killer's path may not touch itself orthogonally or diagonally. The serial killer and "dead" digit may appear within a crime scene in any order. The serial killer never re-enters a crime scene. Some instances of the serial killer digit will appear outside of crime scenes—those instances may appear anywhere along the path, as long as the serial killer travels through the crime scenes in descending order (in other words, the serial killer can "take a break" between crime scenes). One of the digits is Sudokutown's #1 Detective. The detective digit is trying to catch the serial killer but keeps failing. The detective digit cannot appear in crime scenes, cannot appear on the serial killer's path, and cannot appear orthogonally adjacent to the serial killer digit. The detective digit appears in the cell with a star. Some witnesses have spotted the serial killer's path. The clues outside the grid show the sum of the digits on the corresponding diagonal that are on the serial killer's path (digits that are not on the serial killer's path are not counted toward the sum).  

Note there is an example puzzle at the following link: 

https://tinyurl.com/2p9bckzn