My wording sounds odd perhaps because I have got to this point independently of academic philosophy.
Yes that idea is similar to my position, although I would alter it slightly, "if its existence or non-existence makes no difference to that which exists". This presumes that something exists to begin with. As to what I would regard as a "difference", if something were constituted of a substance, that would be sufficient and it would not matter if it was independent of our SPC* including the laws of physics.
Regarding divinity, I don't recognize divinity as generally discussed on this forum here. Although I may be considering something approximating in some way to "divinity".
*SPC=spacetime continuum.