Okay, I'm going for it - Speculation - Agnes is actually the one mind-controlling everyone (Norm only ever says "she," not who she is) because Wanda may be able to do something she can't (like bring a dead person back to life, perhaps this Ralph character she mentions and we never see). She's also there both times the boys age up and (as I mentioned before) she has something potentially sinister to say about the dog just moments before it dies. Perhaps she was trying to manipulate Wanda into bringing the dog back proving it could be done using the grief of Wanda's twins as a catalyst. Only just before Wanda can, Vis shows up. Vis, who has been noticing how Agnes just happens to always be there when it's convenient, have what ever the situation calls for, and isn't actually being controlled by Wanda. Meanwhile, Heyward would be more than happy to dispose of Wanda because he and SWORD were the ones trying to use Vision as a weapon (when Wanda bursts in they have Vis further disassembled as if they are studying him).
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