What am I doing wrong?

https://pobb.in/7oz6syJX1g5F - this is the build guide that I am following (Mid-game)

https://pobb.in/GV8IRmgenw_6 - this is my current POB

when I compare our DPS it's such a big difference. Now my build isn't exactly like how the guide is setup, but it's pretty close and cannot pinpoint where I'm messing up that is creating such a big gap in poison DoT. I'm missing some attack speed on my bow, maybe it's that? In the notes of his upgraded version ( https://pobb.in/OTF-FyITf3O2 - I'm not really focusing his end game versions until I can comfortably clear juiced T16 crafting farms like harvest) he says to switch to CA of Poison but when I did that, my poison damage changed dramatically in POB due to loss of Caustic Ground from normal CA.

Any constructive criticism much appreciated, poison DoT and better survivability is a big focus of mine at the moment. This is my first league and I'm coming from Diablo so I'm hitting a wall with how in depth this really goes in terms of perfecting a setup in POE.

Trying to learn as much as I can, thanks in advance!