Hello Steven,
I think a lot of these faults are not directly linked to a specific part.
When I got mine and tried to do the first service, the garage was 100% that it could reset the service indicator. But then he wanted to charge me extra because he considered the DPF light on as something else. When I persuaded him that this was just the service indicator, he tried to reset but his diagnostic could not do it.
I do not know whether that was just the tool or the guy having no idea how to do it.
When I got an EML at the fuel station, I read online that the problem is from the tank cap. I went to the new garage and he told me the same. But I had tried this and it was not working. He tried his diagnostic and there was no problem could be found. He reset the fault and since then it never came back.
He told me that a lot of these warning may come up even when there is no fault part to replace. For him there was no problem which meant no charge to be made as he did not fix anything.
Do you use the forscan software with the adapter? I think you did well to read that fault being so specific. Maybe the newer car has better firmware that leads you to specific parts. I am not sure if the garage could read something more.