Hey Reema
All i know is that nobody needs to be approved of Govt. of India to open up a immigration business. This is why there are thousands of so called immigration agents or representatives.
ISO certified (also MOL) is more of a company license thing required to register and run a company which is required for any or every comapny established under companies act (got absolutely nothing to do with being in Immigration/visa business)
(source : My knowledge database- I'v got Bachelor's degree in commerce ;D)
All the very best