That's for the last optional chimera scene - if you've done all the others (3 for Meleuma, 2 for Patricia, 3 for the Greenhouse), she appears in multiple screens in the industrial area to trigger it.
However, as a note, versions prior to the current release (16/07/19) had an issue that sometimes occurred when triggering the event, if you're using an older version and want to see the scene it might be a good idea to update before you complete the conditions.