Biggest mistake of Indonesian investigators was to let Boeing & NTSB fella get their hands on the acft parts and FDR/CVR...some " magic " happened!
Sadly because of the state of corruption and disorganisation in Indonesia, local investigators were treated like buffoons. So to get some credibility, they naively handed over a lot of things that could have exonerated the skipper to "people" who worked " magic " over the evidence.
Those fellow Indons who worked the case......it's time to come out of your crummy, yellow back shells!