" * Fixed a bug where Infernal Shade’s Legion node could pick the same enemy multiple times when creating its additional shades. Shades don’t stack so this effectively wasted them" is a quote from today’s patch notes, and I am sure the same mistake has happened to the Sacrifice skill.
Scenario:
-Sacrifice, with 3 points in the “catalyst of horror” node for 6 chains/recasts total
-Bone Curse with the “bone prison” node to ensure having an abundance of minions (the cage pillars are a minion each) within the AoE and thus within chain range
In the majority of attempts (~7 out of 9 cages, 3 sacrifice casts each), three or less sacrifice chains went off. Many times NO chains happened, only one initial sacrifice.
Hence the assumption that a number of sacrifices chained to the same target, but due to the single sacrifices it could also be a number of different things.