Update on theories
(long post ahead)
So if you read next campaign's description "Council Apocalypse", you'll find that the fifth council's been collecting
archaeological data, and also (as seen in the mission "the enemy within") they are looking for the protectors as well.
This might bring a plot twist even bigger than what we've discussing in this thread. What's their purpose? As stated by the raiders, humans could use the protectors' power to be able to warp back to earth and bring with them a bigger army and weaponry so they can easily dominate the planet and its aleph.
But as we know, the canon has it that the raiders managed to find and keep the protectors by their side, which ruins the plans of the council, or not? As i said; Council Apocalypse's premise states they are looking for archaeological information; what a term! As we know, ancient technology is a major element in RotBP universe; and archaeological investigation seems like something you could use to figure out this technology.
Assuming the Fifth Council can obtain enough information about the planet's ancient tech; they perhaps could do by their own means what the protectors are supposed to... (wait for it)
bringing back The Legacy of the Old World. If we assume this is possible, getting to this legacy will become a race between the raiders and the council.
Now let's recall a few facts: the legacy of the old world remains in hands of
Shamash (horned guy, who was referred to by that name in Schneider's showcase stream former to his release) who is waiting for the protectors to open the portal for him and his people. Post credit cut-scenes tell us that the portal has been in fact opened.
Opened... by who? Protectors or Fifth Council? Only time will tell. But to keep theorizing even deeper; what'll happen if each win's the legacy race? Protectors would probably ask just for help to make humans leave the planet (which Harec planned by simply warping them to earth). But council could have a more interesting proposal for Shamash.
In the past; after abusing of the aleph power and technology that led to the break of the planet, the current locals in the planet became pacifists (apart from obvious exclusions), their ancestors expelled from the planet those natives who wouldn't agree with the new philosophies, leaving in exile those who still believe the ancient technology's power can be of good use.
Today; humans are looking to exploit aleph and all its potential. If the Fifth Council gets to recover The Legacy of the Old World, they could ask Shamash to join forces with them; to worship and exploit the aleph with the power of the ancient tech, as the planet's ancestors used to. Current locals' society will oppose; Shamash will have to choose... remain loyal to his own kind, or join forces with humans who support his ways.
I see war coming.