Interesting bug that seems to be going on: you may have forgotten to have the game check for triggers for the 'side with neither, but have Teigan and Hazel both come with you.' event in Dir-Klou. its completely bugged up the Fernia fight in that you can play the fight, and there's a guarentee you can have one of 5 things happen. 1 of which will loop the issue:
1, you will have access to Ysalle's command, Vex's and Hazel's despite Hazel not being counted with that route. meaning the squares they occupy are empty on the command tab. they do what they are supposed to.
2 (repeats) Treats the Fernia battle like Teigan is present for her mid turn attacks as if you were fighting against her in Dir-Klou.
3 causes a overlapping unit glitch where the halbirdeirs are present over Jilliana's swordsmen unit. game treats the unit correctly, and it seems to be an odd visual effect.
4. (repeats) The battle gives you a somewhat glitched ending of the Dir-Klou battle against the Atraxan/Kloutie alliance.
5. Resets you to camp the day of the Fernia battle minus any troops you lost in the battle prior.
A secondary one noticed on the same file is if you go directly to Necrosia from zone 1, and trigger Nadine's side event, it won't let you proceed with it, forcing the outside help event the following day/ several days later.