The difference between what you stated being that Randlemans suplex was 100% legal, the eye-poke clearly was not. Randy wasn't swinging for the fences because of the eye poke, watch the replay. He catches Chuck, who staggers back and Randy makes the mistake of rushing forward and missing a shot which gave Chuck the chance to throw the punch that ended it all.
But don't worry, even if Chuck KO's him again you'll still be hearing about the eye-poke, at least as long as Tito Ortiz has a voicebox.