Hey again,
I would first and foremost check that the script tag is firing on the page/site using Google's structured data testing tool - https://search.google.com/structured-data/testing-tool. Just put in the link of the page where the code snippet exists/fires and this should debug whether or not it has been put in correctly.
Google can be a little picky about branded KG results and it often only shows some of the bigger brands - I would say just be patient and check every now and again? In terms of reviews, if these are associated with your G+, they should appear when your business appears as a knowledge graph or local business result - again, be patient with this as it might take some time.
I would advise using GTM to implement these tags - it's a lot more flexible than amending core page code each time.
All the best,
Sean
