Can I safely assume if the other parts survived then the CPU survived as well?
Unfortunately, without a better idea what caused your MB to die, I don't think you should make that assumption. Indeed, are you certain it was your MB and not your CPU which died in the first place? What did you do to test it to confirm it was the MB?
Fortunately, new Athlon XP CPUs are pretty cheap these days, so if it turns out it did die, you can get one for under $100.
Or you could just use this as an excuse to upgrade to an Athlon 64...