We recently gave one of our cats a deworming pill (milbemax) and later
found a worm (sorta looked like a tan-colored rubber band) in a pile
of vomit.

I thought that tape worms reside or attach to the intestinal wall (and
not the stomach wall) and therefore when the worm leaves the cat it's
by way of the stool.

So is it normal, or unusual, for the worm to be vomited out?