My question involves defamation in the state of: Missouri

My question involves a facebook post placed on a public forum ("I Care About NAME OF CITY") about a performance put on by a local company. The original post included opinions about the company including a statement "[NAME OF COMPANY] in [NAME OF CITY] is NOT on my recommended list!". The person who posted the opinions sent nearly identical content (without the statement of non-recommendation) to the business owner and received a response which began "You are certainly entitled to your opinion," and then continued to state how all other comments received about the performances were positive.

The facebook posting has received 29 comments...all but two of them either sympathetic to the original opinions or recommending a competing company in the same city. The person who submitted the two comments in opposition to the original post's opinions, "put words in the mouth" of the original poster making the statement say something that it neither said nor was intended to say.

Now the owner of the company has sent a private email to the poster stating that she has initiated legal proceedings.

Is a legal threat realistic in this case?

Thanks.