hi Vinny! hope the time flies by!
You probably already know this, but the info you get on a death cert is whatever the informant knew. The informant could be a son or daughter who knows everything about who their grandparents were -- or could be a son or daughter who didn't know or who mixes up which parent is connected to which grandparent set. Or could be a daughter in law or a neighbour who really doesn't know.
I would therefore encourage you to also request the marriage certificate. At least the informants are the couple themselves, who know quite a bit more about who their parents were (although they could still name a step parent or an adopted parent, in good faith because those people feel like their parents or because the bride or groom was only a baby at the time he or she was born, and thus doesn't really know).
After telling you this undermining info, let me also be a bit more encouraging by saying that even when the informant gets it wrong, it can still provide a great clue. Even if the grieving daughter names the wrong grandparent set, at least it could show that you are in the right family....and stuff like that.
Hope the certificates help you build a more complete picture of your family's journey! and with a little luck, help you travel back in time one more generation!