I am surprised at how many people are picking Dunham. He is one of my favourite 155ers to watch, but I think Tibau has better boxing and more power, and can probably take it to the ground if he really wants to as well.
He's a scrappy guy, and Tibau is near-incapable of turning it up and always fights to the level of the guy he's up against (resulting in competitive decisions regardless of opponent), but I think Gleison is just plain better.
29-28. 2 rounds of Tibau punching Dunham and bloodying him up, one round where he takes his foot off the gas and Evan backs him up and wallops him a few times.