It seems, bookmakers keen towards Topuria. I look at the comments and Topuria had higher odds, I think 1.91 will be the final odd or if they increase Volk's odds and decrease Topuria's odds, that will be a huge mental shock for Volk. It probably already is when it moves from 1.53 to 1.91 and you are getting anticipated. Many people even compare this fight to Aldo - McGregor.
Volkanovski is favorite to win but some people are saying he is too old to fight in same level with Topuria so he made great funny video for this, and you must watch it 
It is only two minutes long so you wont waste time, and he did a good job acting and making fun of himself, and I think he earned some money from casino for doing this:
https://youtu.be/C2nsn2uzWog