Here's another shot of him! The picture of the Queen from the bottom left is almost certainly from the unfinished full version intro: the clothes, pose, and setting match up perfectly. The mystery bunny looks just like he does in Radium's shot, but rotated a little; I'm most interested in the upper left rabbit, who is probably Eva (based on the hair) but is wearing something that noticeably is not a dress! There are some little tags next to her, perhaps with color instructions, but they're not legible in the picture.

(Other possibilities, just to be thorough: the upper left rabbit is not actually Eva, but
a) an early design for Lori, given the action pose and rough costume, or
b) a random design for a guest at the wedding, just like our friend the Mystery Bunny, or
c) the Jackrabbits' mother, and the Mystery Bunny is their father, since if Devan is going back in time in order to kill them it would make sense if they were planned at one point to be shown.)