A "doktor" szot is el kellene fogadni
What is the difference between hol and ahol?
The "hol"is a question word, the "ahol" is a place adverb.
But sometimes in literature 'hol' is used in the same meaning as 'ahol'.
Would "Az orvos sétál ott, ahol a tanár vár" also make sense? And if so, would it mean something like "It is the doctor [and not say the nurse] that walks there, where the teacher waits" putting the emphasis on "the doctor"?
Yes, you are right.
Can "odasetal" work in this situation?
IMHO no. The "odasétál" contains the goal, but the sentence only the place of motion.