Redietz, if you want to sue "Rob Singer" for defamation or other legal theory then have at it.
I believe his statements, if false, would probably be actionable.
You are not a public figure.
But I suggest you run it by an attorney knowledgeable in this area and not a general practitioner.
You know Rob's real name but not his address (you'll need his address to serve the lawsuit); you get the address by having your attorney subpoena the info via Dan Druff and his internet provider.
Then file, serve, and be prepared to spend a shit load of money.
Odds are he's judgment proof, but hey you never know.
Your call: to sue, or not to sue: that is the question.
But no empty threats, please: either fish or cut bait.