At this point i don't have any advice. You're already doing the next step. The only thing that could have been done differently would have been to remove the batter immediately and allow everything to dry.
I spilled an entire glass of chocolate milk on my laptop - i'm talking around 4 to 5 measuring cups worth when it was on. I pulled the battery immediately. I had to then tend to my carpet because the laptop is only worth a few hundred dollars at most while new carpet costs a lot more. After about 45 minutes of cleaning the carpet i tended to the laptop which at that point had the chocolate milk gone all of the way through. I would stand the laptop upside down, sideways, and normal and milk would spill out.
After about 2 days of drying and some cleanup work it still works