You are the one who whines about always sticking to scripture, but now argues against the authenticity of verses that say things you don't like. Ho ho ho, what a pious fraud you are!
Sadly for you, the evidence for the authenticity of those verses is overwhelming, so suck it up and deal with what it says.
And its your job, not mine, to demonstrate from scripture that believers cannot have a demon, something you have never remotely proved.
Nevertheless, here's some good teaching, unless you're going to claim these verses aren't authentic as well. But as already posted, you can find similar in Matthew.-
Luke11v24When the unclean spirit is gone out from the man, it passes through waterless places, seeking rest and not finding any. Then it says, ‘I will return to my house, from where I came out.’ 25And having come, it finds it swept and put in order. 26Then it goes and takes seven other spirits more evil than itself, and having entered, they dwell there; and the last of that man becomes worse than the first.”
If demons can re-enter a nonbeliever 7 times worse, do you seriously imagine we should be driving them out of them.
No, clearly deliverance is to cleanse the enemy out of the habitation of believers.