It was soloable @90 before the May 9th update, because the dungeon monster respawn timer was 16 minutes. Now it appears to be 5 minutes. I can kill two of the four Hinge Oils on my BLM, and then the first respawns while I'm fighting the third.

Can you adjust the mission to deal with this, such as halving the number of slimes, or adjusting their respawn timer to be what it was, since these monsters are only for this mission?