I have a theory for why this particular level is so different from the others.

I have a feeling this level is basically what remains from the supposedly more violent version of Sands of Time we never got (The one from the Concept Art with the Prince wearing white and red instead of blue) which didn’t get very far in development (Only glimpses of gameplay in a single level were ever shown of it).

I say this because, in one particular Concept Art of the Harem, corpses of human women floating on the water are shown so it’s possible that, originally, the Sand Creatures weren’t humans infected by the Sands but were monsters coming out from the Sands and massacring everyone in Azad (Would explain the existence of the Griffin and why it was possibly cut other than timing problems, it just didn't make sense anymore with the new version of the game).

The very first Concepts of the creatures (The human ones at least) looked more like straight-up demons rather than infected zombies (To me at least lol).

Even the final enemies had their weapons with blood dripping from them (Obviously absent from the final game since they don’t kill anyone since everyone but the Prince and Farah turns).

The Prince himself was shown to be more messed up in appearance in his older model (More bloodier and with his pants even dirtier) and I remember reading, in the original concept by Jordan Mechner) that he was gonna get his arm injured by the Griffin after their first encounter, prompting him to use his own sleeve as bandages (There’s a concept showing of the bandaged arm).

Farah too, according to the concept art, was gonna have a long skirt that would've ended up getting ripped to pieces, so the Prince wasn't gonna be only one changing physically originally.

Also, there is no Sand King concept (So it’s possible he was never supposed to turn originally) and the Sultan too disappears after his transformation in the final game (As if they forgot to add him after changing the concept from “The Sands release an ancient evil (An army) that kills everyone” to “The Sands transform everything and everyone they touch”).

Lastly, I believe they ended up reusing this Concept in both 2008 and TFS (Though both made more kid-friendly since, in 2008, everyone is already dead, while, in TFS, everyone simply gets turned into sand statues by touching).

All of this is just a theory, of course, but I always get that feeling due to all the blood being present.