Any given system could only be completed by one server or the other. The Fortresses we got from Serenity were because on that server they brought every system to Fortress. We did not. We took multiple systems into Final Liminality. In the same way that we got Massive Fortifications thanks to the Fortresses gotten on Serenity, they got Massive Invasions thanks to our Final Liminality. What this means is if we had been the same as Serenity and had Fortified every system that came up, then every system would have been a Fortress.
There were only so many systems that were eligible. Depending on who you asked it was around 100, which means we were getting pretty close to the end of all candidate systems either way. I think that for CCP the formation of Pochven was a safe bet, and something they could plan for, but players HAVE disrupted and altered plotlines and development with their actions. My issue is that saying it is predetermined, or anything of the sort really cheapens what was truly an amazing milestone in EVE Online and in gaming. Was there flaws? Absolutely. Did EDENCOM allied players get left feeling (rightfully) cheated? Yup. But what we got was three years of development and work by both players and CCP.
Furthermore to assume that CCP would learn nothing from this, in spite of many interviews and other places where developers have lamented many of these very issues, is pessimistic to the point of being unhelpful. CCP has repeated iterated both in Invasions and in Pochven in spite of many people unfounded claims to the contrary. They are interested in exploring what motivated players, and experimenting with making the universe feel more important, impactful, and able to be impacted by our actions.
To this end it is easy to see how a smaller scale event that involves only 8 key target systems could be seen as an iteration based on what they learned from Invasions as they prepare for the next thing. Development time is long, and so adaptation is likely slower than players expect, but the formation of Pochven is still the last “expansion level” event that has happened. Which means while we are due for a new “expansion” (foundations looks promising) it has been less than year since Invasion Chapter 3 even began.
Either way, you don’t have to have hope, good news is the game will develop how it will regardless of if we believe it will work out or not, there are those who feel differently and who are hopeful. There are those in my Alliance that have been calling this the “Golden Age of EVE” because of all the new playstyles and vibrancy to the game recently. It is all a matter of perspective.
All that said to say this, if your going to quit, don’t forget to give me your stuff first. You ain’t gonna need it, right? 
PS: to respond to this -
What chose how was a series of rules based on the Star Type and some disqualifiers like COSMOS systems. So while yes CCP did choose the rules they were not done so with an aim to decide what systems would go to Pochven beyond protecting systems that would be disruptive. The interest in those particular Star types is well founded both is real life astrophysics and in game established cannon.
So yes, CCP “allowed” it to happen, the AI Controller decided when and where to strike. Some candidate systems never got attacked. The AI knew what systems it wanted and would intentionally attack systems that wouldn’t go to distract. CCP referred to this as ‘feinting’. This among other things is how I know there was an AI controller.