I'm writing a process flow at work, and there are a few points where someone has to make a call do something. This could include a go-or-no-go decision, or a decision to roll back to a previous state if the change goes wrong. These decisions must sometimes be made quickly, based on limited information and in a worst-case scenario can have severe consequences.
In my native language (Dutch) we have a word "eindverantwoordelijke" which literally means 'someone who is ultimately responsible/accountable for something'. I'm looking for an English equivalent, but can't find any.
I've looked at other questions on this site, including this, this and this, but none of the solutions provided really fit my need.
Words like 'agent' or even 'decision-maker' don't really emphasise the fact that this person is ultimately accountable (even when a decision is not made, because lack of decision can also have bad outcomes).
Words like 'executor' don't really fit because the person making the decision is not necessarily the person executing the action. For example, the decision might be made by someone in management, but then the action might be executed by an engineer.
Is there any word in English to denote 'someone who is ultimately accountable for a decision or the lack thereof'?