I guess if absolutely nobody else feels up to it, I could DM. It's just that I've only ever been successful when DMing beginners who knew even less about the game than I did. My knowledge of 3.5 is mostly limited to basic core stuff, and when I've run Pathfinder I've had even less to go on. Even with just the core material, I didn't do very well at keeping track of the value of treasure items and figuring out basic economics in the campaign world (rarity of magic items, gp limit of towns).
Add to that the difficulty of figuring out how to run a game online, and that's what I'm up against. But if there's no other choice, I could still do it. Just don't expect it to be perfect or even comparable to someone with more knowledge of the system.