Thanks for your question and contribution.
Your post includes several questions, in summary:
- The nature of the highest divinity or Trinity, and whether its creation is a free sacrificial act or one born from necessity
- Guenon’s critique of reincarnation
Let me start with a short note regarding Rene Guenon.
As we learn from Steiner’s Karma of Untruthfulness lectures, it is important to not only look at the contents of a message and information, but also of its source, who is behind it and why.
Now this is not a judgment of course, but is my impression and humble opinion that Guenon was characterized as an individual by a strong intellectual vanity. As his bio shows (just check wikipedia to start), Guenon – catholically raised and a product of Jesuit rigorous intellectual training and discipline - was negative and fighting the occult movements, the gnosticm, Blavatsky’s theosophy .. on grounds that they were intellectually empty or lacked a good understanding. In a nutshell he saw it as his purpose and mission to give ‘the necessary intellectual foundation for a proper understanding of its spirit’ (hubris, as the spirit one needs to experience in order to talk about it, else it's empty thought forms). And as cherry of the cake, he later converted to Islam as ‘one of the only real tradition accessible to Westerners’.
This gives a good starting point to answer your question, the schism between intellect and spirit .. because we see here someone who takes a dogmatic approach to fight against the spirit in its many faces, and chooses for the fatalism of Islam which resonates with this dogmatic materialistic-mechanistic intellectual view of the work that qualifies as Ahrimanic. (as a sidenote, one is reminded of the big bang devised by the catholic priest Georges Lemaitre, still the basis for why people today think that they Man, the crown of creation, is but a speck in a mechanistic universe). Rudolf Steiner also describes this correspondence between materialism and Islam, materialistic intellectuality leading to fatalism.
Guenon seemed critical of mostly everything, also science, the catholic church .. but in the first place the true spiritual to which he opposed his own true intellectual metaphysics.
It is thus not a surprise to find him fighting reincarnation which is essentially about the eternal spiritual core of Man. For context see Steiner’s lectures where he positions the abolishing of the spirit, then the soul (see more here). And Guenon, imho, like every soul, came with karmic threads as part of (connected with) a certain wave or impulse.
then:
Regarding the nature of the highest divinity, the answer could be quite short. Everyone who has experienced the higher spirit world and the (god-)experience of unity through initiation, will tell you that there is no way to capture or explain it intellectually .. simply because our consciousness, language and intellect is much too limited and incapable of grasping higher levels of consciousness.
You can relate this to the CoC-ladder Schema FMC00.048 on Twelve Conditions of Consciousness (CoC). This is a question about teleology and purpose, and a simple image to express this is to think of the axis driving a car’s wheels, and now imagine this axis tries to figure out what is going on .. why it is spinning so fast and sometimes slow, why it is moving, turning, where it is going, who is deciding on direction, and why? The axis is just at a lower level than the car as a whole, and the human being who devised it and is driving it. Schema FMC00.471A is an illustration of that idea: the gap of 'level 4 trying to grasp and comprehend level 12' is orders of magnitude wider than, say, a stone trying to understand a human being.
That being said, imho the dichotomy might be simply resolved philosophically if one assumes that the act of giving is the intrinsic nature of the trinity, if intrinsic nature can be seen correspond to necessity. Hereby we are going around the problem of freedom, because our concept of free will does not apply to the godhead. Freedom is something relevant for humanity as spiritual hierarchy under development, in its current stage of evolution. At higher CoC stages, sacrifice becomes an intrinsic property as part of creating and giving, rather than receiving.
But my first spontaneous answer above was the most correct, it’s just a question beyond the limits of sensible scope .. as Nietzsche stated, it’s important to deeply question and qualify a problem, so as to focus on the right kind of problems or questions, and so imho this is just a theoretical problem, as they can follow from our faculty of thinking, but beyond what Man can take into current human consciousness .. so, something we should not break our heads on. Also on this point Steiner explains that if one continues to ask ‘why’ there comes a point the question does not make sense any more. Let me conclude with a quote by Rudolf Steiner also regarding your question, from 1903-11-16-GA090A.