I just did this run for three days on two different toons (8.13.13 to 8.16.13) and here's what I experienced:
Snosk: Deferi Patrol 11 o' Clock ( The left from where you spawn )
-I found her three times almost due south of where you spawn and far off at the 6 o'clock position 1.5 squares from the bottom of the green mission area circle
Desna: Deferi Outpost 3 4:30 o' Clock ( Inbetween the bottom and right relays )
-I found her three times in to my right every time I spawned and she was there. She is always on the sensor map directly to my right.
Istapp: Kelvani Belt 2 o' Clock ( A decent distance past the Mining Facility )
-Still the biggest pain in the a#%$ to find. Never saw her at 2 o'clock as I've posted before. Both time she was opposite that position at 11 o'clock. Definitely off the sensor map when you spawn in zone.
So that's what I found. Perhaps the spawn points are changed up to make it even more frustrating to find them. I used a Fleet Support Cruiser Retrofit with all three reputation systems buffs on my Engineering captain. Took em all down in less the 30 seconds. On my Tactical captain it I used a Fleet Escort Retrofit (Defiant..FTW!) instead of my Fleet Patrol Escort . Took a bit longer since I have to manage my hull but the job was done!. All three will drop a Tyken's Rift on you and as we all know that ability is crap whether it's PvP or PvE (IMHO).