When I first watched it, I assumed she meant "we all" to be her, Zulema, and Alex. I have to think she would know better to say than GB did not know "any of the background" since it has been widely reported it was him that was told of Lori's delusions and about all the threats towards CV and about people being called zombies. I am sure he was totally aware of the whole situation by the time the kids were missing (my opinion). Plus even if they had all lived in Gilbert at one time CV and Lori in early 2019, MG and Zulema currently), there must be 100 or so wards in Gilbert, each with their own Bishop.
Having said that, there are two things that made me go hmm and wonder if you could be onto something:
1) If Melanie wasn't in the same ward, how did Lori meet her in the hallway after MG spoke (I reconciled this earlier due to the convoluted relationships/connections many of the pod people have).
2) She said in the interview with Nate at about 6:00 (part 3) she was grateful it was him--what did that mean? See paranthetical remarks of point 1.
Moo.