Jambo, Daniel! Welcome to planDisney and thanks for stopping by with such a great question!
Don't you just love
The Animation Experience at Conservation Station?! My family and I love the whole experience of taking the Wildlife Express Train over to Rafiki's Planet Watch, petting the sweet animals at Affection Section and then sketching an adorable Disney animal at The Animation Experience. I'm so excited you plan to let out your inner artist on your next magical adventure, Daniel! Now, let's get to your question. As Rafiki says, "It is time."
As far as I know, there is no way of knowing in advance which Disney character the animator will be teaching you to sketch at The Animation Experience. But Hakuna Matata! It means "no worries." In my experience, there is a sign near the queue listing the next class's start time and the character you will be drawing. So, on the day of your visit, I recommend checking the class times on the My Disney Experience app, arriving for one of the earlier classes, and checking the listing on the sign in the queue or with a Cast Member. If you see that the character is one you have already drawn, go explore the Affection Section and the rest of Rafiki's Planet Watch and return later for the next class.
As many times as I have been to The Animation Experience, I have never drawn the same character twice. The characters are always rotated around, so while I'm sure it's possible to get Nick again (What a great one!), the odds are good that you will get to draw a new, oh-so-cute Disney animal. My favorite was Simba from The Lion King. I'll be wishing upon a star that you get the chance to draw your favorite Disney animal!
While this likely wasn't the answer you were hoping for, Daniel, I hope it was at least helpful. Please feel free to stop by any time with any questions you have along the way.
Let your countdown begin!
Mandy