I just listened to an episode of a podcast (The Real Weird Sisters) that does character studies on the HP characters where the hosts talked about Igor Karkaroff and it got me thinking about his arc in the series. In GoF, Karkaroff was clearly afraid of Voldemort's return and he was seeking Snape, a fellow former death eater, out for help. It is obvious he didn't want to join Voldemort again (mostly because he was too afraid after ratting some death eaters out after the first wizarding war). He fled and was later killed, presumably by one of Voldemort's followers. So I am wondering why Dumbledore didn't offer Karkaroff help and protection or why he didn't try to get him to work for him. He knew about Karkaroff's fear, because Snape told him about it. We see Dumbledore offer help and protection to others who are or have been on the wrong path, e. g. Draco, Snape etc. Do you think he didn't do that with Karkaroff because he did not trust him enough? I personally wouldn't have trusted Draco either (as his family who he was loyal to was full of dark wizards and witches), yet Dumbledore tried to protect him. Why not try to do the same for Igor Karkaroff? Would love to hear some ideas!

TLDR: Karkaroff didn't want to rejoin Voldemort's side and was afraid. Why didn't Dumbledore, who was privy to his situation, try to help or protect him or try to have him work for him?