Something occurs to me, in relation to the crash, and the speculation surrounding the fuel control switches.
The Indian Air Accident Investigation Bureau's investigators were aware of the potential for a problem with the fuel control switch locking mechanism - they made specific mention of it in their report. So it is absolutely inconceivable to me that they would not have checked for this issue on the part from the downed aircraft.
We know that the fuel control switch module was basically undamaged because there's a photo of it in the report. It is smoke-blackened but otherwise completely intact. So it would have been easy to ascertain if the switch was installed correctly or not.
Having done that, and if they had discovered that it was incorrectly installed, it would be unconscionable for them not to have issued an immediate request for all Air India's relevant Boeing models to be checked for this issue, and to pass the information on to the relevant international air safety organisations, to be disseminated worldwide, as a matter of urgent concern.
However we know that the investigators said that no remedial action needed to be taken on Air India aircraft and no immediate safety concern was flagged up to international authorities, so I think we can be fairly confident that they discovered nothing amiss with installation of the fuel control switches.
The FAA also issued a statement to more or less this effect.
FAA Interim Report Finds No Immediate Safety Issues with Boeing 787-8 in Air India Crash
https://www.eplaneai.com/news/faa-interim-report-finds-no-immediate-safety-issues-with-boeing-787-8-in-air-india-crash