I think that has already been resolved with the latest evolution (devolution) of Rick during the massacre in the church....
Glenn and Maggie did nothing but watch in horror at what went down. I think that's what drove them to leave the group and join Abraham on the bus to Washington..........
Shooting them would have wasted ammo. ;)
And as for Maggie and Glen, they had already given their word that they would go with Abraham.
They were definitely shocked, but I wouldn’t call it resolved, because nobody has spoken of it yet. I think Rick will have to go overboard at least one more time before someone stages an intervention of sorts.