When Furina made Neuvillette her iudex I can't emphasize enough how much she more than likely had to defend and vouch for him. We get a good glimpse of just how against the people of Fontaine at the time were against Neuvillette, especially because of the new laws that were getting passed around, to the point where an entire group of people were forming against him.
It must have been exhausting and terrifying to deal with. Furina loves her people, even with all of the ugly she has seen in them throughout the years, so she must have held steady and steadfast in the face of them being so against Neuvillette knowing that in time they would eventually accept him.
I just think it's neat that it's vague enough to where you can interpret just how much of a supporting system she was for him at the time, but implied well enough to get an idea of just how fierce she was about supporting him throughout all of that backlash and not letting the mob get the best of them.