Act 3 Cruelty - Venom Vial Quest

Hey guys,

I was trying to save my venom vial quest (I completed the quest but didn't select the (+10% to Chaos Resistance, 5 to All Attributes or 15% reduced Slowing Potency of Debuffs) until I decided what I want to do.

Now that I completed act 3 cruelty, it won't let me return back to present time Ziggaurat to turn it in to Servi. Does anyone have any suggest on how I can still complete the quest?