I would like to pose you a question: how could one harmonise the Ascension accounts in Matthew 28 and Luke 24?
Preliminarily speaking, I think that the Bethany location is the true location of Jesus' ascension, since Matthew contains a "then..." which could represent any period of time from a day to two thousand years.
[A COUPLE OF OBSERVATIONS HERE:
1. THE MATTHEW PASSAGE DOES NOT MENTION AN ASCENSION
2. IN ACTS 1.4-6, WE LEARN THAT JESUS MET WITH THEM ON MANY DIFFERENT TIMES AFTER HIS RESURRECTION, MOST INSTANCES OF WHICH HE PROBABLY LEFT BY A DISAPPEARANCE OR MINI-ASCENSION
3. ALSO IN THE ACTS PASSAGE IS AN APPARENT REF TO THE LUKE 24 INCIDENT, SO THE MINI-ASCENSION IN LUKE IS OBVIOUSLY DIFFERENT THAT THE ONE IN ACTS...
SO I DONT ACTUALLY SEE THAT THESE PASSAGES ARE REFERRING TO THE SAME ASCENSION...THE "BIG ONE" IS THE ONE OF ACTS...
HOPE THIS HELPS SOME...