The real shock came in when the spectators realized that this man was in fact Eggman.
But Eggman? Ivo Robotnik? The man that had tried several times to conquer Mobius in the past, and had managed to do so seven months prior, sinking the world in darkness for five long months? Would they feel empathy for him.
Yes, because no one, not even the formerly evil scientist deserved to be electrocuted to death. Plus, there were the many, many stories about him having reappeared after missing for one month after the fall of his empire, having been living on a rustic village for another month until Sonic found him, doing nothing evil aside from installing windmills or something similar and making flying cars for the people there out of the goodness of his heart, followed by repelling a Badnik attack at the cost of nearly dying and, a week later, helping Sonic and the Chaotix detective agency defend Seaside City. In their eyes, that effort was enough to make them give Eggman a chance.
They saw how Eggman screamed in agony as enough electricity worthy of a god of thunder coursed through him, either to awaken his former evil self, to delete his current one, or just plain kill him, they didn't know.
They saw how Vanilla the rabbit, mother of Cream the rabbit and honorary member of the Resistance/Restoration, managed to escape her bound and attack their captor, only to be thrown to the ground through a portal that opened on the ceiling.
They saw how Eggman shrugged the pain and freed himself, grabbed and threw the ginormous Master Emerald out of the room they were in and through several metal walls, and nearly smashed Starline to death.
They saw Eggman sending Sonic away and watching over Cream and her wounded mother alongside two robots, not knowing what to do.
They saw as a gigantic, blue-colored leg crushed crushed the group, causing many of them to scream in horror as they saw the redeemed villain seemingly die.
And then they saw, in a combination of shock and awe, how the robot's leg exploded when Eggman, pretty much alive and, above all, angry, decided that he didn't like being stomped on.
If the yellow-eyed human with glowing, shiny red skin was indeed Eggman and not his ghost or a demon stealing his body, that's it.