The US can't even confirm how many detainees have died in custody in immigration detention around the country, yet they have precise numbers on how many people the Iranian regime has killed? Give me a break.
If Iran is unwilling to let neutral international observers confirm the number, that suggests they are trying to hide a number they don't want the world to know.
Who gets to define what "neutral" is? According to the US, the International Criminal Court is not fit for this purpose. It certainly can't be a nation-state that's in a military alliance with the US.
Human Rights Watch, MSF, UNICEF? Woke grievance factories, the lot of them /s . World Health Organization? US just left it. It's slim pickings out there.