I didn't think he claimed that the OBL raid never happened, just that the backstory about how he was found was wrong.
ISI dealt with bin Laden in the 1980s, and has good intelligence in the region bin Laden had been rumored to be holed up in.
It takes more of a leap of faith to believe bin Laden was hiding from the Pakistan military/industrial apparatus 800 yards from the Pakistan Military Academy, than that some high officials knew he was there.
I don't believe they cut some deal to stage a raid where they came off looking like total morons for purported military aid that never came.