The kings came and fought; Then fought the kings of Canaan. In Taanach by the waters of Megiddo: They took no gain of money.
The Israelites pursued them, and the battle reached as far as the mouth of the tributary Megiddo.  Therefore, allegations that there is some kind of a contradiction here as to where the battle took place are ridiculous. Given the big stampede and the hot pursuit of Barak and his men, the battle was fought in a dozen different places.  See Josephus' account of what happened, above.