This has to be the strangest thing that has happened to me ever. Just started a new game and I'm lvl 2 doing the Goodsprings quests. I go up the hill to get the Broc plant for Sunny Smiles and half way up the hill is a dead Victor! The resident barf scorpion is in his area at full health (until I shotgun him) and nothing else but the 4 bloatflys in the cemetery so I'm clueless as to what killed him. My big concern at this moment is to whether or not the game is useless since Victor is key to the main quest.

Anyone know what could have happened to Victor?

He'll be back at some point. If Victor dies in the Wastes:

Victor is not key to the main quest. He's jut flavour material for one of the main quest paths.
You can continue playing with him dead, won't change anything.

Curiosity got to me so I started a new game and followed Victor after my dialog with him leaving the Doc's house. He goes all the way to the cemetery turns around and comes back. At that particular point in the game the bark scorpion and the bloatflys aren't even spawned, not that they could kill him anyway. I guess this will remain an unsolved mystery but I'm assuming that he must have gotten too close to a giant radscorpion. Interesting that the developers path him to the cemetery in the first place.

Oh well, thanks for the responses.

he respawns at the strip, its ok =P