Putting aside the very poor English here you have a significantly flawed premise. You’re presuming that the Triglavians intend to conquer empire space when all actual evidence points to them targeting only a few systems where the primary stars fit the necessary properties for harvesting.
So even if the Triglavians win every system they invade it’ll only be a subset of empire space, so Concord gonna Concordokken.
Also, conquered systems without Concord response won’t be High Sec anymore.
Also, if everyone chooses to support the Triglavians who’s gonna harvest their loot and salvage to make shiny new ships for you to fly?