Only those who don't want to see certain things and mirror the Russian propaganda line ("we will never know the truth"). This case is pretty thoroughly investigated, down to the names, timelines, and interviews with people who did this.
What's high quality to you? I personally don't consider WaPo, WSJ, and alikes high quality in this case as their investigations are mostly summaries of authorities claims/leaks and OSINT types' findings with little to add, but here you are. [1][2][3] I don't save everything about this, there's a ton more detail floating around, nearly on the same level as MH17.