Does the threat model include malicious system software on the endpoints? Or slightly differently, have you looked at any mechanisms to provide encryption when in use.
Its interesting that in the "long history" of some of these raags, many have moved from folk into the classical realm. To name a few - Mand, Khamaj, Desh.
There is also the diffusion of some classical ragas into wider collective conscience through film music, and other forms of "light" music.
Origins of north Indian classical are much more complicated than attributing to any single person.
There is the Samaveda of antiquity with its puritanical emphasis on metre along with a simplistic sense of melody.
Dhrupad sung in the courts of Delhi during the Mughal times can probably be regarded as the next attested continuation in that tradition.
During the 17-18th century Dhrupad underwent another renaissance and the form of Khayal emerged. One which gave the musician more creative freedom of expression. A large part of what is considered mainstream North Indian classical music today is Khayal.
P.S:
Amir Khusrao's role in development of Qawwali, Tarana and other forms of Islamic Sufi music making sounds plausible. Anything beyond that is venturing into speculation.