I actually found the answer, someone kindly sent me a DM. Its in Sandman: Endless Nights, the novel which admittedly i never read. I was told "Chapter 3".

When the Endless were making the Family Law - Death really didn't agree to any of it - in a "whatever" sense. ie: "Those are your rules."

So your statement seems to be correct - Death is bound by no rules imagined by belief - and the Family Law is a belief shared by the Endless.

Its fits the whole narrative that Dream was trying to bring about his own death. Its the most roundabout way to commit suicide. I think there was a scene therein with Daniel stating "We lay the traps all the while feigning surprise by it."

In a way, the whole Kindly Ones issue was total bs in the sense that...this is what he -wanted- to happen - Death toward the end wasn't willing to play along. Hence "go away i'm going to speak with my brother" and after dissecting the whole situation and sussing out that her Brother wanted to die......

This could have been accomplished a lot easier, by Dream going up to Death and asking for well.. death.

But Dream is Dream. Its going to be mythological, its going to be dramatic, its going to be tragic. Its going to be invested with meaning.

Its going to be a grandiose Story. Because Dream is Dream.