As students we were told back in the 1980s if we were not willing to assist with abortions to be sure we worked in a hospital that did not do abortions- specifically Catholic hospitals. The point being if you worked in a different area - and if you were floated to the department that did- you had no choice. You went where you were assigned or you did not work there any more.
If I was a nurse (and my sister is one), I would say no and dare them to fire me for not assisting in killing a human being. If they dared to fire me, I would go to court and argue the “Nuremberg” rule-—that there is Supra Positive Law (higher law than man’s) that states you can NEVER take an innocent life—even if ORDERED. If most good people did this....fought the evil, it would not continue as a “right”. It would be easy to prove that the fetus was a human being.