Yes he needed to have pressed the TOGA button/lever.
Once P/F disconnected A/T instead (inadvertently) will pressing TOGA create the desired go around?
Will A/T then re-engage or must power be set and A/T re-selected?
Do you ever practice how to recover from an incorrect procedure in a time critical situation?
He could have disconnected the A/P and continued with the miss manually,
but it seems his brain was slow to shift into Go Around mode. Definitely behind the aircraft at that point.