Recently, I encountered the dead body of Magub gro-Orum near the road to Bruma. What he was doing there - I had no idea. His UESP article says that he stays in Cheydinhal so it's very weird that he strayed too far from the town. And I have no mods which affect NPC schedules.

Has this ever happened to anyone?

Npc's occasionally have random, glitches, or otherwise unexplainable deaths. Its a rare occurrence, but you do get reports of it from time to time. Its probably just such an event: Just a rare glitch. Personally I have never had it, but i'd suggest you just move on from it, since it shouldn't cause you any problems.

Envy, like you, I'm mystified. I read UESPwiki the same way that you do and don't see any travel scripted for this guy outside the city gates of Cheydinhal. I've encountered many NPCs on the roads, but they all have some sort of scripted travel package. And I've never encountered this guy outside Cheydinhal.

You've already checked UESP and verified you're not using any relevant mods. One thing I have not done is cracked open his scripting in the CS, but I'd be surprised if that had any travel scripts, given the years that his UESP wiki stuff has gone unchallenged by players.

Maybe all that skooma caused him to become disoriented.

I may be wrong, and just sound like a noob here. But "Random" deaths are found every now and again. Its normally some npc is just found dead for no reason, and its just because of a glitched script. Maybe its possible some sort of script glitches, spawning Magrub dead in that cell? I may be wrong, it seems like an exceptional event, in any case.

If you really have no mods running, its possible you disc is you know, got a one-off fault. A tiny little thing. Its nothing ive ever heard about. Let Acadian or someone else crack open the scripts, and if nothing is found, continue playing and if it happens again, I suggest putting it in the hardware/software forums and maybe someone there can give you an answer.

Thanks guys

My character doesn't care about this character but I was just mystified when I saw him so far away from Cheydinhal.

This.

The problem wasn't even solved in Skyrim, but got even worse. One day, randomly, 2 draugr and a wolf spawned right in front of me when I fast-traveled to the College.