My understanding is that consuming one's soul condemns them to the Void directly. So consuming them is what gave Braccus the ability to call them from the Void. [...]
This is directly contradicted by Wendigo, who wants to get sucked up to escape the Void King, and the same is reflected by countless Black Ring members who seriously scream - and then vanish - if they are consumed.
Hmm... yeah, I see your point. I thought Windego wanted to break her swear to the GK via the Swornbreaker. I don't recall her stating she wants to be consumed to escape him.
After the final fight, should the player choose to ascend to Divinity, Windego comments that she is now hopelessly stuck with the GK and destined for an eternity of torment and agony until such a time that a new Godwoken arises to take the player's place, and to the seal the breach between the Void and the world of life for good.
I must be missing something as it doesn't add up to me anymore. Windego is, at the time of freeing her from the magical cell, still living and thus sworn to the GK prior to death, right? Perhaps being dead and then consumed is what sends them to the void. All I know for sure, I guess, is that dialogue with a spirit (iirc in the graveyard in Act II) the option to consume their source states, "Consume the spirit's source, banishing it to the Void."
Not really sure what to think now? I suspect that it is because she is still living that is the key. Perhaps being alive and sworn is only possible because of the breach between the Void and the living world. If so, then choosing to sacrifice Source and close the breach would free those who are living and sworn. It seems logical to me that consuming the souls of the dead would cause them to scream and panic if they are in fact being banished to the Void.
I'm currently under the impression that the souls of those who die feed the barrier of Source between the Void and the living. I really might be misinterpreting the dialogue here too, so if I'm not correct then I apologize.