What went wrong?
Catalyst of Horror → allows sacrifice to chain to 2 targets.
Sanguine Libation → Increases chain count by 1 per point.
In actuality, Sanguine Libation overrides Catalyst of Horror and SETS chain-count to 1-5 per point. This means that with 1 point in Sanguin Libation you have 1 explosion, instead of 3.
With full investment you have 5 explosions instead of 7.