Jack can certainly fall victim to Edmen's furious flurry of violence in the first, he's just such an awkward striker that even Vettori managed to knock him down and, even though I love Marvin, that's not a good omen when it comes to fighting a prolific finisher like Shahbazyan.
On the flipside, I don't think one camp is enough to fix the problems with Edmen's game. In fact, a more passive approach might be his undoing in a matchup like this, against a guy who can and has been overwhelmed before.
Back in the regional circuit Jack was known for pretty much playing with his food to an extent and scoring late finishes time and time again, regardless of the quality of his opposition. That suddenly changed once he realized he could simply pin guys down and go ham on them and beat them into submission, usually hitting a wall against guys that had him beat on physicality.
Santos, Cannonier, Vettori and even Ferreira were quite simply better than him athletically, with some having technical advantages over him in other aspects to boot. Is Shahbazyan in the same league as them? Yes and no, I do believe he has the athleticism to negate Jack's offense early, but the gap on the feet isn't as big as it was between Jack and Cannonier, and I doubt he'd command the grappling advantage Cezar and Marvin did.
Having said all that, I do favor Edmen slightly due to how good he can be early but I am picking Jack to gut out a bad start to pull out a late finish.