Hardly. Indian English is not even very different from some dialects of British English (just not the one British dialect that most non-Brits are used to). Even many of the features that people commonly associate with Indian English are actually taken from British English and still present in present-day British dialects (again, just not the one that most non-Brits are familiar with).

There are other dialects of English that are far more different from Standard American English, to the point where an American speaker will have trouble understanding them altogether, as opposed to being able to understand the meaning correctly albeit with noticeable distinctions.

But you're right that there's a good chance that this is a dialect difference.