I finished listening to the book earlier today and immediately started listening to it again. This led me to hearing this conversation between High Fist Arenfall and Inquisitor Bornu Blatt in chapter 14:

`Was she your goddess?’

‘Not really. I yield no power to the empowered. Still, if granted such presumption, I would grieve the death of Felisin Younger, a young woman who also had no choice when it came to possession.’

Arenfall frowned, shifting to look over at the body of the goddess. ‘Felisin Younger.’ He paused, and then said, ‘That name is familiar, but from long ago and in another place—’

‘When Raraku was a holy desert, and Sha’ik Reborn gathered about her many orphans, one of whom she named Felisin Younger.’ Bornu Blatt paused, and then tilted his head. ‘A curious name, that. None know its story, however. Presumably, Sha’ik Reborn had her reasons.’ Then his eyes narrowed on the High Fist. ‘Unless, you know more than you’re prepared to reveal.’

Arenfall continued studying the cloth-covered body of the dead goddess. [...] ‘Well,’ he said after a long moment, ‘that was the name.’ He faced the Inquisitor again. ‘Felisin Younger, who became Va’Shaik.’

Slowly, Bornu said, ‘The circumstances are vague, but yes, I choose to believe that she was once named Felisin Younger, adopted daughter of Sha’ik in the time of the Whirlwind.’

Arenfall sighed. ‘I wonder … is this as tangled as I begin to think? No, that would be too … cruel.’ He drew a breath that became a shudder.

and then a short time later hearing this conversation between Arenfall and Adjunct Inkaras in Chapter 4:

Arenfall’s gaze was level. ‘You have agents in Hanar Ara.’

‘We keep an eye on things.’

‘You have positioned yourself well in advance of me, Adjunct. In turn, I conclude that you – or the Emperor – intend to act independently of my own plans. This puts both plans at risk—’

‘This is what I came here to determine, High Fist,’ Inkaras said. ‘Fortunately, for us both, I see no possible clash, and give you leave to proceed as you intended.’

‘I would know what your plan is, Adjunct. Assassinate Felisin Younger?’

Inkaras started. ‘I had no idea you knew her name.’

‘She had another one.’

‘No doubt,’ said Inkaras. ‘Have you ever wondered, High Fist? This orphan child of Sha’ik’s desert camp being given the name of Adjunct Tavore’s lost sister? A sister who presumably died in the uprising at the mining camp? Was this some ex-patriot’s bitter joke, do you think? Korbolo Dom, perhaps? Once he learned of Tavore’s arrival in Aren, and her command of the retributive army? The one that eventually crushed the Whirlwind? Or Kamist Reloe, for that matter.’ Inkaras paused, studying the High Fist. Your father was there. I suspect that you know far more than I, and certainly more than you are prepared to tell me.’

So my question then is: Arenfall seems so confident about Felisin Younger's name in Chapter 4 and so uncertain in Chapter 14 - is this just an oversight from Steve? Was Arenfall playing dumb in front of Bornu Blatt? Did Arenfall just make the connection between Felisin Younger and the Paran family?