I am reproducing the question content hereunder.
How can these questions be answered from Hindu scriptures or even
commentaries of acharyas, outside of their own opinions?
The topic of interpolations belongs to the field of textual criticism
and not Hinduism, let alone Hinduism stack exchange, where we answer
As a matter of fact, it is impossible to prove whether a verse,
chapter, or scripture is an interpolation; you can only guess with or
without confidence whether something is interpolated or not.
Moreover, one can claim that something was redacted or omitted from an
earlier manuscript just as easily as one can claim that it was
interpolated into later ones.
So these kinds of questions are not appropriate for this site and
should be closed as opinion based. In some cases, they actually were
closed as opinion based.
Basically, these type of ideas will crop only when ONE thinks that everything that is available in EPICs, Puranas, etc, are to be taken on FACE VALUE.
No. They should not be taken on FACE VALUE.
If we accept them in toto, we will be doing unjustice to ourselves and to Sanatana Dharma.
The disowning of Sita episode is available in Sargas 115-117 of Valmiki Ramayana.
In this episode, a deliberate attempt was made by subsequent writers to project Sri Rama and Sita as the incarnations of Narayana and Lakshmi.
भवान्नारायणो देवः श्रीमांश्चक्रायुधः प्रभुः || ६-११७-१३ एकशृङ्गो
वराहस्त्वं भूतभव्यसपत्नजित् |
"You are the Lord Narayana himself the glorious god, who wields
the discus. You are the Divine Boar with a single tusk, the
conqueror of your past and future enemies."
सीता लक्ष्मीर्भवान् विष्णुर्देवः कृष्णः प्रजापतिः || ६-११७-२८ वधार्थं
रावणस्येह प्रविष्टो मानुषीं तनुम् |
"Seetha is no other than Goddess Lakshmi (the divine consort of Lord
Vishnu), while you are Lord Vishnu. You are having a shining dark-blue
hue. You are the Lord of created beings. For the destruction of
Ravana, you entered a human body here, on this earth."
Here, we can cross check with Rig Veda, Brahmanas, etc, the slokas mentioned above, and can easily deduce that these Sargas 115-117 of Valmiki Ramayana, as interpolations.
Nowhere in Rig Veda or brAhmanAs, it was mentioned that Narayana and Lakshmi are DIVINE Couple. It was the product of Puranas.
In Rig Veda, Rudra was mentioned as DIVINE boar, but not NARAYANA. There was no mention of NARAYANA in Rig Veda. In brAhmanAs, it was Prajapati, who took the form of Boar.
Except in the interpolated areas of Ramayana, the word Lakshmi was not used to indicate the DIVINE consort of Vishnu. It was used to indicate riches only.
In their anxiety to describe Sri Rama as the incarnation of Vishnu, those writers forgot that in subsequent generations, like ours, an accusation will arise about Sri Rama as male chauvinist.
This is only illustration of an interpolated version in Ramayana. If we study deeply and cross check with available scriptures, we can easily find the interpolations.