“Yes, it was a real kingdom in that it exists in the real world with real people and real buildings. Even with that being true, it’s still a false kingdom in that it is built on lies and deception (from Satan and the Antichrist), even though it’s “real” in the sense of being in the physical world.”
Well, Satan must of been able to deliver the goods or it would not have been a real temptation. If Jesus knows it all lies and deceptions why be tempted?
As to your other points, based on the information I have read regarding these things (ghosts, ufos) without fail, it seems people who testify about their experience are non-christians or very unorthodox in their beliefs. Also, these people are usually involved with the occult.
There is a LOT of overlap with the occult.