The memorial was supposed to be voluntary. If you chose to undergo the experience, cool. Janeway fixed the broken warning buoy, and flew off. This is what happened in Caretaker. How can she trust a buoy to keep transponding for the next thousand years, if she can't trust a timer on a torpedo to wait 30 seconds till after she's left the quadrant to blow up caretakers array?
The buoy is going to break down one day, allowing the memorial to start raping people again.
She should have left Kim behind as a Caretaker.
But at some point he'd need to have a baby to take over his job to stop the memorial from raping unprepared starfaring aliens, because he's not very immortal at all.