No, that was just Trianna changing into a different costume.
Jackson Publick indicated Kim doesn’t have any screentime in Season 3, if memory serves. Nor does Baron Underbheit.
Trianna certainly made Deans day with her “You’re so cute” comment. And Dean tearfully shouting “YOU’RE NOT POLITE!” while beating Dermott had me rolling.
A quick note on the Tee’s I ordered one of them and emailed a week later to find out what the standard shipping time was and Jackson Publick responded. So apparently he ships out the shirts himself. Oh and his response ended with “We love you”.
Damn. I’d much rather have the Baron around than Hatred.
Had we ever before been given a hint of reciprocity?
Man, I can just see Dean going villainous super scientist to get her attention later on. Especially after Dr Z’s comment - there’s definitely an angry streak there.
Well, she doesn’t avoid Dean like the plague. Frankly, that’s enough of a hint on its own. 
If you visit the Adult swim website, they now have the ep. with “director’s commentary”. It’s worth watching. They reveal the “real world” inspiration for Sgt. Hatred (Large, crewcut guy watching porn on his laptop in a starbucks), where Pete White was (He was the voice on the PA. His announcements tell a side story, but you can’t hear it.), and their plans for the new kid (regular character, to provide contrast and possible shark jump)
Good stuff.
How do you get the directors commentary?
Try http://www.adultswim.com/ivc/venturebros/ep30/
Also, the next ep. “Dr. Quymn, Medicine Woman” is up. Early for the 4th, I guess.