Greetings Mike,
Your question isn't really answerable as you pose it, because each nidana is a misguided sankhata by-product of (personal) ignorance, yet you seem to be implying that in the case of rupa, it is partially not, and thus somehow the public aspect of rupa is affirmed by the personal samsaric delusion known as paticcasamuppada. I contend it is not so. The four elements are so, or "such", but not due to paticcasamuppada.
Rupa
should be viewed as empty and non-substantial, but due to ignorance, it is not. Specifically regarding form, as per the Buddha in SN 22.95...
Phena Sutta wrote:On one occasion the Blessed One was staying among the Ayojjhans on the banks of the Ganges River. There he addressed the monks: "Monks, suppose that a large glob of foam were floating down this Ganges River, and a man with good eyesight were to see it, observe it, & appropriately examine it. To him — seeing it, observing it, & appropriately examining it — it would appear empty, void, without substance: for what substance would there be in a glob of foam? In the same way, a monk sees, observes, & appropriately examines any form that is past, future, or present; internal or external; blatant or subtle; common or sublime; far or near. To him — seeing it, observing it, & appropriately examining it — it would appear empty, void, without substance: for what substance would there be in form?
And as previous discussed re: MN1, phenomena
shouldn't be extrapolated from noumena
“Bhikkhus, a bhikkhu who is in higher training, whose mind has not yet reached the goal, and who is still aspiring to the supreme security from bondage, directly knows earth as earth. Having directly known earth as earth, he should not conceive himself as earth, he should not conceive himself in earth, he should not conceive himself apart from earth, he should not conceive earth to be ‘mine,’ he should not delight in earth. Why is that? Because he must fully understand it, I say.
... Yet due to avijja, we do. Because we do, we find them mentioned in paticcasamuppada.
Because of ignorant projections of "phenomena" onto "noumena" (of the variety warned against in MN1), it is relevant to include them in "rupa dependent upon ignorance", because that is what people mistakenly believe they are grasping. Yet it's no more "real" than the jati attributable to I-making etc. which people, under the spell of avijja, will believe is a literal post-mortem rebirth.
Nothing is ever proven as objectively true and valid, by a process which at every turn is dependent upon ignorance. This should be common sense.
People generally don't realise they're grasping at name-and-form, and not the four elements. This is why nama and rupa are conjoined in paticcasamuppada, and not presented separately. It is the objectification itself which one "contacts", and later grasps at.
Metta,
Paul.