What you are leaving out is that governments can choose whether the ICC definition of warcrime applies to their territory. Iran has chosen that the Rome treaty, and the ICC, does not apply to Iran. It has even used this fact to request the ICC drop cases against them.

We all know why: 99.99% of warcrimes on Iranian territory were committed by Iran's islamist regime.

So Rome statute warcrimes are a legal impossibility in Iran. The Rome statute, that law and that definition of warcrime does not apply to anything happening in Iran.