You can see the results in 'fetch as Google' and in the structured data tool. Injected JS content is there, including changes to the page title and head.
As always take SEO advice from Google with a grain of salt.
Well, is SEO advice just allows you to get rid of any impediments from rising to where you should in the results then you should trust them, but if SEO advice is a thing that can help you rise to a prominence that you should not have then that advice would be detrimental to Google and they would not give it to you.
So really it matters if you believe in the light or dark sides of the SEO force.
Why?