Nadleeh wrote:However, what possible issues could I be facing?
If you power it up if there's still some liquid in there, you might cause a short circuit. In the long run you might suffer from sticky keys that don't work properly anymore (sugar in the drink, mostly) and damage to the circuit boards such as corrosion/rust (any acid in the drink and water in general).
It would probably be a very good idea to clean the inside of your instrument properly (or have it done by someone). Even if the liquid itself has already dried up, residue that is left in there can cause more damage over time. Unfortunately, to do it properly your Nord needs to be disassembled quite thoroughly; removing the circuit boards fixed to the top panel (with the knobs) to check for any spillage (and clean it up) and taking apart the keyboard (really only necessary if you have sticky keys and/or you see any gunk in there) are the two major chores.
While it is not necessarily hard in a technical manner, you need to be rather careful (and systematic) to avoid doing more damage (i.e. electro static discharge) or to have parts left over at the end. Ideally this will be done by someone experienced in fixing/cleaning keyboards, but someone who's handy with taking electronics apart, cleaning them and reassembling them should be able to do it too. Whoever does it, it might take a few hours depending on how much of that drink actually made it inside.
I recently bought a used Access Virus TI. While testing everything seemed fine, but when I came home it turned out several keys were sticking (of course the guy I bought it from kept insisting it wasn't like that when he sold it to me). I took the whole thing apart, cleaned out all the soft drink (judging by the smell it was something like Cherry Coke, Dr Pepper or Foots) with some q-tips (cotton swabs) and some rubbing alcohol (isopropyl alcohol) and reassembled it again. I'm pretty handy with stuff like this, but I think it took me more than 8 hours (granted, I probably took it further apart than was required).
Unless you're confident enough you can do this yourself, I wouldn't risk it. Either leave it as it is and hope for the best (who knows, perhaps the worst thing you're left with is a funky smell) or have someone else (with the right skills/knowledge) do it. I don't think hardcore electronics skills will be required though.
Regardless of whether you're going to clean it yourself, it might be a good idea to open her up to check how much of that drink is visible inside. If you hardly see anything it might be okay, but if there are like pools of liquid in there it might not be
Anyway, I hope you get this solved; it would be a shame for that (elderly) red lady to go out of commission.