Joanie:
I can only think of one reason the cutting would cause a branch to wither and die, (although there may be more). The scissors might have had a contaminent or a disease. A while back I pruned a forest of Serissa and sent the cuttings to some of the forum members if they donated to the forum. These were just cut and rolled in wet paper towels, put into a plastic zip lock and mailed. At the same time I placed a few cuttings in water and they all rooted.
When I root Serrisa in water, in a bright area, but not direct sun, they develop plentry of roots, I plant them in a fast draining soil. I have used several mixes such as half Lava and half wood chips or third Chicken grit, third haydite, and third wood chips. Both recipes worked fine.
Good luck to all Serissa fans!
