I want to preface this to say, I don’t know the likelihood he would have actually one, so ill put it at like, 1% Maybe that still controversial, since its the doom slayer, but, his entire plan didn’t have any inherent flaws, and he behaved rather smartly around the doomslayer the entire time, although he was not as smart later onwards in some of his choices, I think we are forgetting that, he STABBED the doomslayer, its been awhile, but I dont think davoth was able to wound or make the slayer as vunrable as Azrak did. Like, stabbing the doomslayer is FAR from a easy feat, and during the fight we see him fight back quite well against the doomslayer, parrying some of his attacks or barely reacting to his FISTS, which is supposed to be the more powerful part of doomslayer, I am talking about enhanced Azrak only as regular Azrak stood no chance, I feel like, if he didnt kill his dragon, his odds would have improved, not by much, but would have improve, and if he didnt want to “prove” himself and rather PREPARE more, he could have increased his chances maybe more, although to be fair he did think he could rival the doomslayer, but he pushed his luck. Also, he is the only villain in doom, who had it together, but fell due to some bad decisions in the end. He started off the attack by telling his forces to avoid the slayer, nobody else did that. Betruger and Olivia were greedy and was just manipulated. The Maykrs never really did have control, Davoth just slapped some stuff together and hopped in a mech in fear of a slayer, I dont know if Davoth was smart through his whole ordeal. Its also likely that Azrak would have lost to the slayer, no matter what, and this is probably what the lore might be leaning towards, I know the current eternal slayer is unstoppable, but idk about the earlier slayer

TLDR: If anyone had the faintest chance against the slayer, it would be Azrak (or maybe a wraith but thats a seprate topic)