Opening to Receive, Not Establishing a Connection

The Dharma provides two precise mechanisms for how the dharma-flow works.

From outside: the compassionate aspiration of all buddhas pervades the dharma-realm without gaps. Empowerment appears not through temporal retro-transmission, but because the dharma-realm has no gaps. Initial aspiration is the moment of "opening to receive."

From inside: the Dharmapāla-Xuanzang lineage accounts for buddhahood by innate undefiled seeds in the ālaya-vijñāna. But that same lineage distinguishes five spiritual lineages precisely by whether such seeds are present at all — the Cheng Weishi Lun: "the distinction of lineages established by reference to the obstructions is meant to show the presence or absence of uncontaminated seeds: if there are no uncontaminated seeds at all, the seeds of the two obstructions can never be destroyed, and such a one is established as outside nirvāṇa" (T31n1585_p0009a21–a23) — and so does not say that all beings stand alike. The tathāgatagarbha scriptures state the universal case instead: "all sentient beings without exception have Buddha nature" (T12n0374_p0407b09). Both readings are transmitted side by side. For one in whom such seeds are present: The potential for buddhahood was always in your consciousness-store. Initial aspiration activates those seeds and lets them begin directing your stream of consciousness.

These two mechanisms are the outer and inner faces of the same event.

From outside: dharmatā pervades → aspiration = opening → empowerment appears.
From inside: pure seeds present → aspiration = activation → seeds direct the stream.

No retrocausality needed. Because dharmatā isn't in time at all.