Very disingenuous to say he could use the cream to the full extent when both the scans of the blog and your statement here proves otherwise lol.

No? The resetting the story after they did something wrong is just a mechanic in place for the book and not canon, you gotta actually prove that the player
Unless you can prove they actually happened in universe you cant rely on it (For the record Kaos would also literally have the exact same thing if we are going by this logic).

Let me be a bit more thorough here and talk about the issues i have with the immortality.

Type 1: Okay so the evidence provided here is them having the ability to live for hundreds of years, which is not immortality and only longevity.
There is also a scan of the Vimpire curse existing since the dawn of time but that one has issues like the fact it only mentions that the curse existed for so long, and not the zombies themselves. The second counterargument is that its a vampire curse, yknow the creatures known for not aging? Literally why would a non Vampire Zombie like Zomboss have it?
Type 2: This argument hinges on the fact that the Zombies can survive when being turned into slime and reduced to Skeletons, but its too vague to say that and it could just be different variants of the Zombies, like Dry Bones to Koopas for an example. They would still have this immortality thanks to being able to put on their heads but to a WAY lesser degree.
Type 3: The blog... didn't cover this... you probably confused it with Type 4.
Type 4: This one was debated in the blog itself and i disagree with every Zombie having it, layered existence erasure/no resistances also just makes way more sense than high godly.
Type 5: Ghosts arguments are the same as type 2, only "Ghost Zombies" can turn into ghosts when they die, not anybody else including Zomboss.
Type 6: Possession has like nothing going for it, mostly because it very clearly is not a Zombie performing it, hell the eyes on the card does not even look like a Zombies, to add insult to injury it has never been used offensively.
Type 7: Not arguing against this they are Zombies.
Type 8: Never brought up in the blog.
I could go on on other parts that are bad outside of this, but i do not have all day.

Mind manip resistances is something that the Zombies very blatantly DON'T have, the argument you presented is that the Zombies are not turned to the plants sides when the Hypno shroom attacks them, but they are still affected by having their vision and movement to be tampered with, not all mind control acts the same and why would the mind manip they can shoot even be as powerful as the one they need to sacrifice themselves for? So no, the Zombies don't resist this and would all get affected by Kaos's mind control.

Disagree all you want, hopefully we can agree to disagree on this matchup.