Right now I am at about the end of chapter 8 in Seralwi's route, and am having some trouble.

I have no clue how to finish quests 83 or 86. The area for 83 isn't showing up after I fought her, and I have no clue what I need to do to finish 86 with is counting as an auto fail if I go to the next chapter. Also Ragsmuena has yet to join my party, even after I did all her quests. I've tried looking through most of this forum, both wikis, and gamefaqs. I am now close to the end of my rope in terms of what I can think to do.

For quest 83, after you beat Mylen at the workshop, you need to ask around the city for a while.
For 86, you need to recruit all non-NG+ party members (12 total) and have Wil at level 60.

You need Yuela at level 38 to recruit Ragsmuena. Transcending resets the character's level, so all level-dependent events won't trigger until you get the necessary level again.

Okay, just tried getting her up to level 38. And nothing, no real changes.
Edit:Just figured it out, the event in the workshop for the wigs made it so I didn't notice whether or not Wilfred had any events separate from it.