Trade in return

I wouldn't risk it and unless you have another Note 9, I don't think it's going to do you any good.
 
I have a new unopened Spen for the Note 9 in yellow if anyone is interested.
 
When I return my note 9 to Samsung, can I keep the S pen? Or will I not get the full $600?
It's probably all or nothing on the $600. I would see what the trade-in instructions say. Unless they specifically state that the S-pen isn't needed, I'd include it.
 
When I talked to Best Buy yesterday about the Trade-In... What they told me was if there are scratches, cracks or any other imperfections the price would be adjusted accordingly

That being said, you can buy a note 9 SPen on eBay... probably for less than the amount they will dock you for turning it in without it