Customer Q: Can Reviews ask for a review through Google or another platform?...

Customer Q: Can Reviews ask for a review through Google or another platform instead? Or as well as on jobber?

A: At the moment, Google is the only supported platform because it's where the vast majority of customers are searching for your business and reading your reviews.

As for the difference between Jobber Reviews and internal feedback left through the job follow-up feature, check out this answer.