Sisters of Garukhan did not reward +10% lightning res after defeting them.

Bump

Might be too late now, but I thought I had the same problem, turns out its not an item like other times, it is given automatically.
There is a message in the chat window saying "You have received +1-% to Lightning Resistance"

just tried it and got no buff

I too am having this issue, and despite what has been said, While I DID 'receive a message' stating that i gained 10% lightning resist, that has not been reflected in my character sheet.
this is NOT cruel difficulty, I have no passive nodes reducing my resistance, I have no items reducing it.
My resist is precisely as the sum total of the equipment I wear indicates with no deviation.
The character simply has not been provided the benefit promised.

Confirm. Even after patch 0.1.0e, they do not give a bonus to resistance after killing sisters.

Still does not work.

It says I got +10% lightning resistance in the chat window, but when I take all my gear off, I still have 0% lightning resistance.

Same for me. it did not work

Same. I see the message in chat but got 0% resist with nothing on.

same here
this is for both the 10% resist of lightning and cold on the sisters of gharukan and the ice witch in act 1
currently in act 2 as of checking