I recall Nathalie to sit in a circular cave room: approx 53,100 (bottom of map)
She's in the middle of the room together with the Hive'regal rubbing. Remember to get Glyph Chasing so that you can get rubbing at same time.
Room is populated with some elites that can be pulled sep. There are also 2(?) swarms with non elites at her back. Dunno if they add if you try to kill her. She's easily sap'ed and you can get rubbing without pulling any of the elites/swarms

Edit: Did her yesterday. No swarms but 2 of the elite wasps seemed to be linked. Watch out for Slavemakers Mind Control. As a rogue I used lots of DoT's, hemo and a fair share of stunning. Nathalie spams fear/MC too.

NB! In a comment for the quest "The calling"/Emissary Roman'khan somebody wrongly claims this quest is a part of that chain.