"Payback" war question

[Agent]

I'm playing the Payback start on Grand Admiral / Scaling to 2300 and I had just started my Payback/EndThreat war against MSI in like 2330 when a Great Khan emerged in a place my borders literally surrounded. This was not ideal. I was forced to cancel the war, figured I'd just go ahead and do it once the Khan was dead... but MSI just joined a Federation with 3 other civs around the galaxy while the Khan is still doing his thing.

Does that mean when I launch the PayBack war I'm going to have to rampage across the entire galaxy wiping out all 4 (MSI+3 others) civs? They'll all jump in when I declare war and I'll have an "End Threat" war going on against everyone yeah? D'oh.

[Titanica (MAGA) (MASA)]

I believe so.

[Titanica (MAGA) (MASA)]

All for one, and one for all.

[Agent]

That's a shame.

You're either with me or you're against me I guess.

[dakkagords]

Yep, I had this in the relatively early game (2300 I think)

By the time I was done, I'd hammered 5 whole empires into oblivion. I broke some of them back of as vassals, but i was surprised when I finished off the last of MSI and all their allies kept fighting.

[Agent]

It popped off and, yeah, I had to crush 5 empires. Including the "Broken Shackles" guys who had promised to also declare war on MSI when I did. They were in the federation with MSI (idiots) and apparently that overrode their promise.

But there's a problem somewhere. As far as I can tell there isn't a single sector or planet in the entire galaxy owned by the MSI federation and vassals that isn't conquered and occupied, but I can't get the war score high enough to win. Relative naval strength apparently caps at +50 so that means +100 attrition, +50 naval, leaving another 50 that has to come from occupation.

Except occupation is stuck at 41 and I am poring over the galaxy map over and over and over again looking for unoccupied planets and I can't find any. Some other ♥♥♥♥♥♥♥ empires jumped in when I declared war and occupied planets... does that mean I have to declare war on my "allies" to supplant them as the occupying forces on MSI+ally worlds?

Maybe I'm missing something about the system but that seems sub optimal considering I can't actually accept a white peace in a payback war, meaning I can never end this war?

[Elitewrecker PT]

Yes, being occupied by people in separate wars prevents both sides from achieving full victory.

[Agent]

Yeah, I recalled all my fleets and sat around for 5 years until one of the wars sputtered out into a white peace, then flooded back across the border and snapped up a few more planets in like 30 seconds flat to get over the threshold.

I think I made a mistake in that I used my armies to take the enemy core planets thinking it would get me a surrender faster, but given their core planets were heavily defended by armies it meant major casualties and slow going. I think I should have just scooped up a ton of weakly defended planets instead of fewer heavily defended planets and this could all have been avoided.

But hey we got there in the end.