Given that the gig is under Cribb's rules, I can see no justification for making Spinks the favorite. Any narrative that did so, would just require too many assumptions.
You are describing a guy as a "mall ninja" but it depends on how the story is told. Steve Jennum was the defending UFC champ when he defeated Bowen. Jennum had won UFC 3 and was undefeated in MMA. UFC 3, was a one night UFC tournament where a guy fought until he either won it all, or lost (I know the circumstances).Jennum was still undefeated after UFC 4, in his entire MMA career he never had to go past 1 round. His performance in UFC 3 inspired Georges St-Pierre to compete in MMA. (https://en.wikipedia.org/wiki/Steve_Jennum#References). Steve Jennum was the first person not named Royce Gracie to win a UFC championship. Jennum weighed 215 pounds. "Mall Ninja" or legend of MMA? It's all in how you tell the story! If you're counting double-leg takedowns, Whitehurst took Liston down too!