Probably because Tank is really about 5'3 or 5'4" almost every pro athlete inflates their height. Fury is another bad one, he's about a half inch taller than Wilder not the 2" he's listed at.
Rollie has a good troll game Going for him to win as I can see what they're trying do with Tank manufacturing him to the core.. But realistically Rolly has about 5% chance