Sanskrit and Tamil are complementary to each other. Almost all original sanskrit texts were burnt by muslims so there was some hope there of finding some concrete links,if we had those texts i.e.
https://www.myindiamyglory.com/2017/09/11/nalanda-9-million-books-burnt/
https://www.youtube.com/watch?v=TwmJQBQP4lA
Theres this professor who could provide some info,and some other informative discussions ,
https://www.youtube.com/watch?v=N3D9_F83Gus
https://www.youtube.com/watch?v=C0KMXbtoTcg
https://www.youtube.com/watch?v=wpML4ZLuxRw
https://www.youtube.com/watch?v=enfZZvQ5AB4
https://www.youtube.com/watch?v=e8OTfay7a2I
https://www.youtube.com/watch?v=wvdNckoR4WQ
A lot more info on this channel (long videos and presentations),
https://www.youtube.com/channel/UCaUSUD4yxwEalbsP1rhjo0w/videos
An informative book,
http://booksdescr.org/item/index.php?md5=3CB188560531BCA763990712E874FB02
All of confusion stems from Academic Hinduphobia(Pagan phobia) of the jews who're translating and interpreting such texts like Wendy Doniger and Sheldon Pollock . Theyre misguiding the readers into believing something the text does not mean,mistranslating it or outright lying in some cases. I hope you find something interesting in the swadeshi indology source i provided ,HPMageson.