No, only drachnids see invis. There are very few of them, this entire quest can be done with out ever being attacked or invs broken.
Ada SUCKS!!! You should not have to worry about someone else triggering the spot before you. My quest is my quest and should not be impacted by someone else's quest. When you have 5 or 6 other people in the zone doing the quest then you are having to drop the quest and requesting the request over and over or you are running around over and over trying to find these mythical spawn points you have found.
Unless the queen is up....every damn time I help someone with this task she is up! Bet if I wanted her for hunter she would never spawn! Lol
Quests are trival and loot always drops when nobody needs it. If someone needs anything, difficulty increases to the point you start looking at the clerics dps parses.
Find some spots that are not listed on EQResource, and thus used by most of the EQ world. Besides the first spot (which i have never waited on) there are probably 50 spots for this quest at various steps.