I did and it was the same as ending the converation at any other point.
Although good news! I did manage to reach the 0 conviction result when I tried again with hypnosis and got -11 conviction (and maybe higher trust?)
That sounds pretty strange, perhaps it's a bug. I'll be looking into it next week.
I reviewed the event and didn't see anything strange. However, if Nersmias' trust reaches 0 or less on the same round his conviction reaches 0, you will be locked out of the route to talk to Sillan at no cost.