Whatever he had expected to hear tonight it was not that!
Vance is about to turn around and head back upstairs, not sure if he's been insulted or not when Ducky spots him and waves for him to come inside. Shaking his head he turns towards the elevator, and waits impatiently for it to get there so that he can collect his turbulent thoughts. His face flushes with embarrassment as he imagines what the conversation had been about.

Honestly do none of these people think of protocol, and the ME being the one to instigate it all! He'd never have thought it possible. The ME being too gentle and mild to even suggest such things.

Downstairs just prior to Vance's departure:

“I was thinking about getting the Oyster, you know Mother always did like those. Or the Blackman, depending on her mood.”

“Hmm those do sound good Ducky. The 99 really sounds good. That raspberry sauce all over Mr. Whippy and the pointed cone.” Jimmy says enthusiastically.

“The Bunny Ears...a double 99...delicious and I'm so glad you mentioned these tonight Ducky.” Ziva is practically moaning in ecstasy.

“I think I prefer the Blackman, mmm, with that chocolate-coated part and oh, yeah that sounds really good.” Tim smacks his lips.

That's when Vance had fled Autopsy vowing never to step inside again without a prior notice. Ducky looks at the other three.

"Do you think he knew we were talking about ice cream treats?"