They must think that nobody reads the Scriptures. I do not have the Kamba Ramayana, but I have the Padma puranas. Lord Rama"s return is described in the Patala-khanda. And it does NOT say anything that remotely suggests that Sri Rama ordered the destruction of the setu.
In any case, the Kamba Ramayana is a relatively recent book, written in Tamil by Kampan, who lived in the 12th century. It is well-known that he took many liberties with the original. It is easy to see why the Congress cites this book as proof.
