I don’t think this dispels the myth at all.
1a. Outside of Charlie Villanueva, I don’t think any player is going to talk about specific, offensive trash talk that happens during a game.
1b. Even with a specific incident such as Charlie Villanueva, there were 10 guys on the court, and the only one that heard anything was Villanueva apparently. You never heard stories about other players (other than KG) denying or confirming it (or maybe I’m remembering wrong). Unless it’s in a somewhat positive light (like Jordan said he’d dunk on you, then he did), you don’t ever hear about it.
2. If it did happen, would you expect Tim Duncan to openly talk about it? He doesn’t seem like the kind of guy to mention postgame or ever after the fact. “Oh ya that time KG talked about my dead mom…” Unlikely to happen IMO. If it was something that was that over the line, I would also think it’s the kind of thing you’d never want to talk about again. Also Duncan doesn’t seem like the kind of guy to hold a grudge and bad mouth KG at every turn (though I know he’s not friendly with KG).
3. “The story goes…” has nothing to do with it. “The story goes Danny told Red he’d trade Bird.” “The story goes Larry went into the locker room before the 3pt contest and said I just wanted to see who would finish 2nd.” “The story goes” is how a lot of 2nd hand events get retold. Doesn’t make it untrue, it’s just means there’s no concrete, accepted-as-fact source on it. And how would any legit source break this in the first place? You have a ref, and probably 6 players around the free throw line, they would have to tell a reporter, who would report the story which can’t really be verified. We have legit sources breaking the Charlie Villanueva cancer comment, yet we still don’t know if it’s true.
4. You want verified sources, we’ll there are plenty of sources and polls ranking KG as the league’s worst trash talker. Multiple players have talked about their dislike for him (Duncan, Noah, etc.). How do you think he got that reputation? Not by saying non-offensive things.
5. And when you hear the story, does anybody say, “Wow, that’s totally unlike KG.” Anybody who knows about him, believes he could say it.
Now I know none of these things make it’s true, but at the same time it’s pretty hard to throw this out as completely false.
One of those things we'll never know I think, because I don't think either player involved would talk about it.