LSSJ Broly

If u ask me.. Yeah...far more than 7000...About 19-20 million years ago (u can calculate time from 24th treta to 28 kaliyuga)

Also, have a look at this. hinduism.stackexchange.com/q/16693/26679

spaceoftrueindology.quora.com/CLARIFICATION-ON-THE-TERM-KŌṬI spaceoftrueindology.quora.com/…

About 33 koti devatas...We have different opinions here...Some believe as you said and some believe that 33 koti devatas are actually present. You can see a post which I linked below

As I said before..I cannot predict about modern science on this buddy :)

Regarding modern science and carbon dating...Umm..I cannot say much because science is still developing itself...what if science says tomorrow that this info was wrong..And something else is actually the truth. For example.. how The models of atom were developed

I personally believe that it happened in treta yuga..And sorry it was 24th treta yuga..Not 21st..We are in 28th kaliyuga..

So he was born in treta yuga only if you believe in yugas. Even some other scriptures say..If I recall correctly.... that in the 21st treta yuga of vaivasvat manavantara, shri rama will take birth.

One more thing...I would give you a genuine advice that don't depend on wikipedia for getting informations on Sanatana Dharma :)

Modern historians and ancient sages have different things to say. You cannot link modern theories and traditional things everytime. :)