Her whole return to the Queen of blades was based on the fact that she thinks hes dead and has more of a reason for revenge.
But it was pretty obvious he wasnt dead from the get go. The news report said he had been interrogated for a short period of time and then executed, but all the showed was a picture of his armor with a bullet hole in it.
We see her in the dropship trying to contact Raynor, and not being able to. She also is unable to sense or hear him (something she USED to be able to do as QoB), so yeah, in her world, considering how badly Mengsk had been gunning for them both, it was altogether believable that he'd been executed. Remember, in WoL, Raynor is the Dominion's #1 enemy even BEFORE he goes tear-assing through Zerg space to rescue Kerrigan.
Also, it's important to understand the relationship between Mengsk and Kerrigan. It starts WAY before the events of Starcraft 1, notably in the novels. Kerrigan was one of the three Confederacy Ghosts responsible for murdering his family on Korhal. Mengsk hunted down and killed the other two, but recognized the immense power that Kerrigan possessed, and chose to turn her against the Confederacy. The battle of New Gettysburg had Kerrigan there placing Psi Emitters to lure the Zerg into destroying Tarsonis (thus cementing the fall of the Confederacy). By leaving Kerrigan behind to be killed (or so he thought) by the Zerg, Mengsk was basically killing two birds with one stone. The death of his family would be avenged, and the Confederacy would fall by one of their own weapons.
The original Queen of Blades was the product of the remains of Sarah Kerrigan being brought to the Overmind, and being warped into their own super-soldier. Her bloodlust for Mengsk remained, but the rest of her compassion, humanity and soul had been seared away. That is who we knew in Starcraft 1 and Brood War, and who mercilessly hunted her enemies, and betrayed all that she knew and loved. She was the murderer of Fenix, and the scourge of the known universe.
The primal Queen of Blades that we meet in Starcraft 2 is an entirely different person. She retains the memories of her past, but this is Sarah Kerrigan's own destiny making the choices. That is why she spares the escaping transports after killing Warfield. That is why she chooses to land her troops outside the civilian areas of Korhal, despite knowing it would make her battle more difficult. That is why, ultimately, we see that Raynor -does- still believe in her humanity. She is Zerg, she is the Swarm, but its Heart is still human.
So they torture soldiers in full combat armor? On top of that, Raynor was number one on the terrorist watch list. You think they wouldn't have made his execution the most public thing in the universe?
I think you're reading too much here. They used a photo of his armor with a bullet hole in the visor. Pretty sure they can still Photoshop something like that in the future :D
That and not seeing Duran are what upset me the most about the HotS story. Though i am glad Kerrigan is back to her Queen of blades form.
We see Duran, just not as he was. Nurad is commented as a shapeshifter, and has been involved with the Hybrids. There was a secret mission in Brood War where Duran is basically starting the beginnings of these, and we hear Kerrigan that she "recognizes" something familiar on the platform where they battle.
I do agree, I -REALLY- wanted to see him morph back into his red beret during the cinematic. Overall, meh, it's still doable. In Brood War, Duran admits that he serves a darker and higher power than Kerrigan. Obviously, it was Amon.