You're 100% correct -- I meant to refer to wetting agent.
When I went to search for the source recommending the addition of a wetting agent to the Tetenal stabilizer, I discovered that this is a subject that has been beaten to death on this and other fora:
My posts weren't meant to throw any more rocks at an agitated hornets nest, but instead share a couple mildly amusing anecdotes from a C-41 newbie. In any event, 1) I get to remix some stabilizer since I accidentally dumped it; and 2) adding the Photo-Flo to the stabilizer had zero visually noticeable effect on the negatives. They dried well, without spotting or water marks.