This is what you get if you zoom in on the blue-ray version and screenshot it.

Well.. actually I just paused it and took a picture of the screen with my cellphone.  Turned out well..

So we got a good back shot.  

Unfortunately by the time I got this good shot, I had already made a lot of the back panels from a poor dvd version of the same shot.  Google didn't seem to have a good one.  Oh well..

Did the same thing for the next angle.

Good front shot, mostly.  There was one more closeup shot of his face, but it really didn't add much to the data.

We are in business, minus the fact we never get to see him from the waist down.

But we have some references there..

So it looks like baby Groot has similar bark panels for the lower torso to adult Groot.  Less toes smaller panels, and more branches though.

His butt is a bit more mysterious.  It seemed to change from shot to shot.  I decided to also model that after adult Groot.

So that was the plan: build the upper torso and face according to the shots, and build the lower leaning towards the structure of adult Groot with a dash of baby Groot.