I am 100% with your post - except I am not sure what you mean by the last sentence. Are you saying that as a result of the exorcism, the demon falls to a lower/darker place in Hell?
As you said, how do angels move! To determine such a happening in its architecture is difficult to assume or to even make a logical guess.
Fallen Angels communicate via electrical impulses - felt through sensory modes that go some way to enabling us to experience the world temporally - (though I am not a scientist) stimulated in connection to the psyche (I think) and so there must be communication taking place, in which demons, from the place of Hell, can communicate with souls on this dimension of existence. This would remove the word ‘movement’ from the language we use to describe the actions of angels on a supernatural level.
If demons communicate from Hell, so to speak, then this tallies with the last paragraph regarding the opposite - a place of sanctity. The same rule applied…
So, if a specific demon communicates itself from Hell, with use of its intellect and will, but then chooses to fall back - if they choose to attack then they choose to fall back -
because the demon cannot handle the light omitted from the exorcism, then it does appear to correlate with the fall from Heaven. Demons cannot go back to a place of sanctity - if we recognise this correlation as a valid theory - because satan and the demons could not go back to Heaven, once they fell.
By using such a rule, we are then applying responsibility onto each person’s individual will in assurance of it being a place of required sanctity, as well as theoretically placing an account for the existence of each and every demon.
Now, after having chosen to attack a person’s will, and having fallen from the light of an exorcism, as the consequence, the demon is most-likely unable to re-enter that place. If we understand that demons attach themselves to our psyches, which are not perfectly in tune with our intellects on earth, and that this has probably been the case for all of our lives, then it is highly possible, that the person who had to have an exorcism, had always been under the influence of, or under attack from, a demon/demons, and so, the exorcism has brought about a renewed state of being in relation to those demons or that particular demon, and quite possibly freed the victim from all future influence from it.
As for a demon falling to a lower place in Hell. I don’t know. I think at present, it is more likely that a demon can still attack others but just not the same person. That said, maybe it is, that once thrown back, or better put, once they have thrown themselves back, in response to an exorcism, maybe this action then limits their existence and communication to a boundary: if they are faced with the light of exorcism and then fall from it, this is the equivalent of stating that they have again distorted their own intellects as a consequence of the process of exorcism.