So fucking close.
Spoiler: show
Setup:
Spoiler: show
SBs used:
Lenna - USB2
Dorgann - BSB
Bartz - USB1
Galuf - CSB
Kelger - USB
I've had three runs using this setup that went 90%+. It's mostly an all out offensive build with the minium mitigation I could fit in. I put Lenna and Kelger in slots 1 and 5 to help mitigate critical in phase 1 since I can't fit in protectga. Once last stand up is up later criticals are aren't as dangerous.
Edit:
Finally got him. I switched out earth sabre for power breakdown on Dorgann to help with the physical attacks. I also got real lucky with some double and triple casts in phase 4 and 5.
Spoiler: show