My Hypothesis is that this is a Life vs Machine, sort of scenario.
Demon the Descent p52
Some demons believe qashmallim are angels that somehow
escaped the God-Machine’s control and now operate under
a different set of principles. Whatever the truth, these beings
resemble angels. Instead of serving an alien intelligence that
craves order, however, the qashmal exists to foment change —
whether in the form of growth and evolution or entropy and
chaos. Additionally, qashmallim do not require Infrastructure to
bring them into the world or sustain them.
Wise demons steer clear of qashmallim just as they avoid
encountering angels. A qashmal will not attempt to apprehend
a demon to bring him back to the God-Machine, but it is still
a powerful supernatural entity with an unknowable agenda. It
is likely to do anything, and its actions probably won’t benefit
demons that get in its way.
Like angels, qashmallim are single-minded in the pursuit of
their current mission. Occasionally a clever ring of demons
will engineer a collision between the mission of an angel and a
qashmal and let the two fight it out. Manipulating two powerful
angelic beings into attacking each other is exactly as difficult
and dangerous as it sounds, however.
Chapter 2 p56 of Pandora's Book is entirely on the Qashmallim and The Principle. Like the God Machine the Principle has several proposed theories (none of this is set in stone, but rather supporting some further theory)
The Principle is not an intelligence, it’s a Darwinian
force. The Principle is the cosmic blueprint, a kind of
fundamental, ultra-terrestrial DNA chain that governs the
single organism of Gaea, the world organism. The Pyros is
the spark of Gaea’s life. It exists in a morphic field that joins
and enlivens all the biomass of the planet. At some point,
humans created flaws in the systems that govern Gaea. Some
Awakened. Some bred with spirits, creating beings straddling
two realms that should by rights be separate. Some died and
remained living, becoming parasitic tumors, lesions on the
planet’s biomass. And some somehow managed to harness
the morphic field itself, draining it into Created beings that
perpetuate themselves endlessly.
The qashmallim exist to rectify this.
The Principle is a quasi-intelligent agency, a God-Machine
that maintains universal balance.
the Qashmallim are composed of Pyros, this is highly unlikely to be true of Angels.
My thought is, that The Principle is perhaps a God Machine, but not the God Machine. And perhaps the Principle created the god machine to move the progress of the world forward. However, at some juncture the God Machine started to malfunction or its interpretation is different(maybe like Skynet the only way to end war is to end all life).
Matthew McFarland states in a reply on one of the previews for Promethean the Created 2e
The Principle is not the God-Machine.
it is also hinted at that we may get some suggestions in this edition about the relationship, but no "truth" will be given.
This weeks update for Promethean 2e, by Matthew McFarland, was on the Qashmallim
Qashmallim are not Supernal Entities (they’re born of this world’s Pyros, not the Supernal Realms of platonic forms) and they aren’t the servant-slaves of the God-Machine. Some demons, “Unchained” former angels, theorize that the God-Machine’s servants were created from qashmallim their master somehow captured, but the God-Machine’s commands are not the Principle, and its angels burn Essence, not Pyros. As such, if there is a relationship between the God-Machine and the Principle, it’s not one that the characters in the World of Darkness (who are, for all their power, limited in scope) able to understand. Put another way, you’re free to decide that relationship.
and then specifically on The Principal and The God Machine that's Matt's own Head Canon and will probably never be codified as fact.
In The World of Darkness According to Matt: The Principle was first. The Principle is many things – the spark of humanity, the desire for human connection, the lightning that created life from the primordial soup. Throughout the first few billion years of Earth, it was evolving along with all of life, looking for…something. It was undergoing its own Pilgrimage.
Once humanity arose, it found its purpose. It was able to shape servants – the qashmallim – from its endless reserve of Divine Fire, and send them into the world. Unfortunately, its own commitment to self-determination meant that it can’t really control qashmallim; they always have a bit of autonomy (which is why they fail sometimes).
Somewhere along the way, someone created the first Promethean. Might have been Hank, actually, or it might have been some collection of rocks arranged into a human form that some caveman, lonely after the destruction of his tribe, created. Who knows. But at that point, the Principle’s real purpose was cemented – guide the Pilgrimage of the Created. That is its chosen expression of its purpose.
And then there’s the God-Machine. The God-Machine is from the future, but the thing about time travel is that it’s irrelevant when it happens, as long as it does. The God-Machine has its own agenda, but its agenda is a lot more complicated than the Principle’s. In order to interact with the world, though, the God-Machine copied a lot of the Principle’s “software.” That’s why its angels always have enough free will to Fall.