The security issues all would stem from the imagery simply being available to the public at all (and even then it's a stretch, most criminals/terrorists whatever will likely scout an area before doing anything anyway). I don't see how adding intermediaries adds the slightest bit of security at all. Could you expand on why you think it would?
As for Google collecting data itself, it's only collecting photographic imagery that anyone else can.
Google was funded by the CIA ( https://qz.com/1145669/googles-true-origin-partly-lies-in-ci... ). It was part of the PRISM project where American Tech companies worked with US intelligence services to share data with them. India (or any country for that matter) would be fools to allow Google vans or any similar setup from a foreign company to allow them to scan an area (do electronic surveillance) and give them a blatant pass to photograph and spy on secure government facilities on behalf of US agencies. (US agencies that have worked to sabotage India's R&D in the past).
As I ELI5-ed in another comment:
To understand the hesitancy of the government, recall if you've come across any secure government facilities any where in the world - most such infrastructure will have a common warning painted or posted publicly stating "Photography is prohibited / not allowed". Allowing the process of collecting street view data (i.e. taking photographs / videos of a locality) by foreign companies would make such warning redundant and a joke, even if they didn't use the data in their applications - they are not even supposed to have such data in the first place.
Yes, terrorist and spies can certainly try to reconnaissance a secure facility themselves. But obviously the job will be harder to do undetected given the security guards and cameras. In fact, in the 26/11 terrorist attack on Mumbai, one of the terrorists caught mentioned that they had used Google Earth to familiarise themselves with the locality before they attacked - https://en.wikipedia.org/wiki/2008_Mumbai_attacks . Once that was revealed, there were immediately comments on how Google Satellite view is a threat to indian security. But the indian government didn't ban Google Maps satellite views because they understood this technology has become mainstream and they just reviewed their security policies and adapted it. With street views too, the government has finally come up with a decent policy - allow indian companies to collect and process the data, let the intelligence agencies review the data to remove sensitive information or even put in fake data to confuse anyone with nefarious intentions against India, and then allow anyone (including foreign companies) to license and use the data. That's a very decent compromise that Google should be happy with.
As for Google collecting data itself, it's only collecting photographic imagery that anyone else can.