Well by possible I mean it is within the realms of possibility, not that it is very likely. I am sure they have tested for this kind of thing. I've read of a couple but usually that was the result of crew opening an armed door into a jetway or catering truck and the slide deflecting back into the cabin.
What might make sense is some sort of anti-deflection projection / protrusion / enlargement etc. so that no matter what, the inflated slide cannot jam itself back into the cabin.
Not sure how practical this is.