Just to go back to the OPs original question.
If your airlines has no SOP about using TOGA (or any setting above CON) in the event of a longwinded emergency turn, then I suggest you ask what they want you to do.
My suggestion would be to leave TOGA (or any setting above CON) where it is until A) you are above MSA, or B) terrain separation is assured or C) the emergency turn is completed.
Would anyone disagree with the above? Or would we all like to hit the hill, but have nicely under stressed engines?
Practicalities ladies and gentlemen.