Not sure if it’s a bug or it works as it should.
You have two identical particle systems with the same seed number. The only difference between them - one has enabled sub emitter component (it’s empty, without actual sub emitters). It breaks the seeding, spawn positions become different. But if You enable sub emitter component on another system, then the seeding works just fine.
It seems that other components (didn’t test all of them) do not break the seeding.
So my question: is that a bug or a feature? IMO it’s a bug.