As a Christian myself, I know Christians who say we shouldn't get even remotely involved with this kind of stuff. But I always remind them that Sun Tzu was correct in that you cannot win a war unless you know your enemy. I remind them that the Bible agrees with Sun Tzu in this regard and tells us that we must be aware of the wiles of the enemy.
That said, though the Bible is a powerful and ancient book, many Christians are like people everywhere...they are not keen on using their noggins when they study it (see tagline).
BTW, if you have a link to a video of Montalk and the demonic aspect of so-called aliens, I would like to watch it.
What I can give you is a pdf of this book by Montalk:
https://montalk.net/files/fringeknowledgeWEB.pdf
His discussion of demons and comparing them to aliens begins in Chapter 8 “Higher Negative Forces”. Chapter 9 then focuses on aliens.