I think you could actually just throw the two-liner in hormah (with no rescues on it) die by numbers, put a counter on the two liner, then immediately put it under when Hormah activates.
No, you cannot. Battle resolution, including discarding EC, is a step.
After that step, you surrender a Lost Soul. You cannot activate Hormah based on a discard that happened previously. It must be resolved immediately on the discard, that is, before surrendering a soul.
However, if you gave them half of the Lost Souls card then AotL an EC in your own territory, their SoG/NJ could not interrupt Hormah. They would be bottomed.