Ripley 8 barely cared about the people she was with on the Auriga, and barely remembered Newt. I highly doubt she'd remember (let alone care about) Morse.
Morse could have been killed pretty much at any moment. Golic could have hit him too hard with the fire extinguisher, he could have died in the quinitricetalyne blast, he could have been run down in the tunnels, and the W-Y team could have shot him to death. Hell, he almost got stabbed by Junior (I think) running with scissors, only to have the Alien take Junior out when it very easily could have killed Morse instead. Like I said, Morse's survival can be attributed more to luck than anything else.
Hell, that's a bit of a recurring theme in 'Alien3' - very few of the characters had any control over their own deaths, other than Ripley and Dillon (and Bishop I guess, and maybe Aaron although I don't think he expected to get shot). Hicks and Newt start the trend, and it continues through the whole movie. Morse had about as much control over his own survival as someone who survives a F5 tornado ripping through their house.
