A charge cannot declare a trigger as its not a duel. A horror type duel fo the charge is separate and is not triggered in this case anyway as the duel would be defensive in nature for the Yasunori in this case i.e. being able to charge and IRC there are no triggers that would be relevant anyway as certain abilities (e.g. Kang) may allow it to be ignored.
This is a corner case situation as not many instances of 1 AP Charge are around and if it was a straight Ml /Ca/ Sh attack, then its clear that no tigger could be declared. Its my view that its the intent that the actions taken from Promising Whisper, if they are consequent to another action would be limited in the same fashion.
Don't get me wrong, I'd love for that to be the case, but I just can't see that it was the framed inent to allow triggers for subsequent actions.