The main problem for AiG in that link is their timescale, unsurprisingly. Although Sanskrit and the European languages can be recognized as having common roots, the difference between Sanskrit and Latin, for example, should only be about the same as the difference between French and Spanish, or perhaps slightly greater.
Sanskrit and Latin have less than two thousand years to diverge (after Babel). The French/Spanish divergence and the English/German divergence could be seen as 1500 hundred year divergences, about the same. But I bet that Sanskrit and Latin speakers could understand virtually nothing of each other's language, whereas we can make easy sense of a lot of German words, and the French equally of the Spanish.
This is because the real divergence of Sanskrit/Latin is probably about 4000 years, meaning around 4000 years B.C.
Adam and Eve's days!
So they'll have to think up a lie to explain the profound difference between Sankrit and Latin in less than two thousand years.