I'm not sure I understand your question. Astroturfing is getting online and posting positive stuff about the product while posing as many unaffiliated persons on forums, review sites, social media, etc. This creates an appearance of high popularity and user satisfaction, and like astroturf, you can't tell it's "fake" from a glance. This creates a buzz that causes real users to pay attention and join in.

Since this company was targeting Facebook, if they wanted to astroturf, they'd do it by taking control of many Facebook accounts and posting positive stuff about their product in niche groups, on the product page, etc.