There was no conversation, per se. I sent him you post, exactly as written. I also sent him my revisions and asked for the ruling on the second sentence being incomplete. I was then told that as written, in a paragraph, the sentence was o.k. as written.
Now, as for your example, it does not apply, as the sentence in question is not a stand alone sentence. It is part of a written conversation, included in a paragraph.
As for the original post, I revised it to correct grammatical errors, much the same way you do to everyone else here, relating to spelling. Not placing commas in their respective places is incorrect punctuation.
So, even if we take what you call the incomplete sentence out of the equation, you still made punctuation errors. It's pretty petty to point all of those out though, isn't it?