NPC Leveling Fei Yin Bats - Double XP Weekend

I got a level 90 NPC (halfway to 91) that I need to level and the best bet for it is the bats in Fei'Yin near the Qu'Bia Arena zone. Since these mobs are decent challenge to 99, its also a good place to skill up as well. I plan on making the most of this double xp weekend to level up my npc. However, soloing takes forever, especially when I'm still working on capping blue magic (404/424).

Below is when I plan on being in Fei'Yin this weekend:

Saturday: after 18:00 CDT. I have to work during the day (mandatory overtime FTL). I plan on getting tactics pearl quest done before bedtime.
Sunday: all day after I get out of bed.

best place any T+ for 99... aka Gustav Tunnel, T/VT Worms/Adamantoise 2.5 lvl per call.