What a really smart observation. The scriptures don't say a great deal about Satan......they say enough to make us aware and really no more than that. We are to be aware, not to be ignorant of his ways and resist. God doesn't give Satan a great deal of PR and what we can take from that is that our response should also be proportional. Satan is not to be our focus or fascination.
I am not really sure where TWI got all their information on the devils kingdom or methods, but I do know that much of what they say and believe doesn't come from the scriptures. Not without a great deal of reading into them with the wrong focus. Imagine what they miss with such a skewed vision?
Satan fell from heaven because he wanted prominence. TWI simply gives him what he wants.....