Too Much Time in the Raid

Undermanned teams = RNG + time. It's what you knowingly choose if you go in with less than a full team, with specific exceptions (like Tarkin/Scorch at R9). 

I run 5 teams, only Tarkin/Scorch is undermanned. The only team that has significant RNG that usually requires a few attempts is BB2, because they're garbage in the raid below the R9 tier. Tarkin/Scorch, KB/JN + 3, JMMW lead JV and my 5th team atm is Maz lead Pirates. The last raid, BB2 cooperated and I got the max score run in 2 attempts. The other 4 teams were all straightforward max score runs on the first attempt. I spent ~30minutes on the raid. 

Three hundred  attempts on KB/JN? That is insane. You're either trying a duo on R8/9 tier or you have absolutely garbage mods. Not building a few more JVs for the KB team may have saved you some relic materials, but it's certainly costing you time. I built 8 R8 JVs for the raid (I already had KB and JN R8 before the raid teams were figured out) and I don't regret a single one, not even QGJ. Both JV teams score 2.7mln in one or two attempts (sometimes I lose a key toon on the opening to DCTs' massive damage, that's unavoidable RNG).