It's gotta be that worthless snake Gregory. By way of him whispering in Simon's ear probably.

 

Nobody, he is just fishing for info.

 

Gregory

 

I am guessing its the garbage gang leader.

 

I already know SPOILER ALERT it's Tara's finger
But being serious I think it's the leader from the garbage pail kids she might've looked for the saviors to see what the group they were gonna be fighting looked like and made a better deal and this is probably how it went. Jadis : Me want gun Savior : what the hells wrong with your speech Jadis : Gun want Rick attack Savior : What? Jadis : give gun rick bad

 

I'm guessing Simon. he probably told negan about his talk with Gregory at the hilltop

 

Jadis has to be behind it.

 

But Jadis is with Rick on the wall of Alexandria, in what appears them getting ready to face Negan.

I think it's Eugene. Unless the timeline is way off, Gregory did not leave to talk to Simon until after Negan said that line.

 

Eugene was taken when Spencer and Olivia were killed, that is what spurred the rebellion in Rick, Eugene doesn't know Rick is planning to fight.

 

Jadis is seen on the wall of ASZ with Rick but this does not eliminate the possibility that she is the birdie. I mean, she and her men could turn against Rick from the inside.
In the promo, Dwight is seen standing behind Negan too. So, Jadis might be acting as an undercover for the Negan team just as Dwight being one for the Rick team.

 

Jadis is mixed up up up.

 

This is the thought I had. Negan is no dummy - he could easily be playing Sasha.

 

I'm thinking Eugene. He has been converted. He says as much to Sasha. In Negan's camp, for the first time since the world went to hell, he feels safe. If he believes that is his best chance for a future, he would not want to see Negan go down. He would warn Negan about the coming rebellion.

 

Enid. Because Romulans.

 

I think he just had some scouts monitoring and saw Alexandrians had guns.

 

Either Junkyard crew or Gregory. But, more of my money is on Junkyard