Since states in India are essentially divided based on linguistic grounds, he would have been exposed to two Indian languages at best - the regional language in his town and Hindi (if the dominant language in the town is not Hindi already).
In the Bay Area you'll find people from various states of India.
Doesn't the same thing happen within India itself, due to internal interstate migration? Not everyone who works in (for example) Bangalore's IT industry grew up there.
In China, the purpose-built electronics city of Shenzhen is full of migrants from other regions, so the local language is Mandarin even though the surrounding Guangdong province speaks Cantonese.
Among white collar workers English is pretty common.
I've discovered that they generally share the same native language when they are from the same region in India, otherwise they don't. The only exception I've seen so far in Punjabi, since it seems that Delhi also has a significant population of Punjabi speakers who have migrated there from Punjab, which is farther to the west.
Sometimes my coworkers do share languages, and that's obvious if I hear them speaking to each other in a language other than English. Sometimes they have to speak English to each other because that's their only common language.