I have read both versions. My personal interpretation is the killings definitely happened, however there are a lot of grey areas and unknowns around what exactl

I have read both versions. My personal interpretation is the killings definitely happened, however there are a lot of grey areas and unknowns around what exactly happened there: who did it (the VCs/the armed civilians/the South Vietnam army/the US), who died in those graves (militants/civilians), the circumstances of the killings (military executions/mob justice/lynching/casualty from fighting/bombing), etc. Perhaps the truth is a bit of everything. This will unfortunately remain as one of the tragedies of war that we will never know the full picture of.