I'm a Bangladeshi and I don't trust my government a singe bit. Still, I believe that while these numbers may not be exact, they are not wildly off the mark either.
Considering that the dead have not being piling up anywhere in India, I'd say India has succeeded in managing it all.
Whoever controls the narrative, decides on what numbers to report.
Do you think the government would have been able to hide the large number of deaths that would have occurred, if the death rate was the same as reported by Europeans and Americans? It's not easy to hide a large amount of bodies, given that half of the country is ruled by political outfits that oppose the central government.
The dead bodies in real life don't just vanish into thin air like in star wars.