I haven't checked myself but if I remember correctly I believe Nettle's page on the wikia mentioned that she can be seen below in the pit when Woundwort addresses his officers.
I went back to watch that scene. Assuming this is the right one:

Well that's dark. While there are clearly rabbits down that pit, I don't think I could identify any of them...
But assuming she is there, this would strongly imply that she became a prisoner following the escape. Considering how she spread false information given by Hyzenthlay, Orchis probably wouldn't trust her anymore.
Considering the horrible conditions Efrafan prisoners are kept in, this would probably result in a slow and painful death for her. It probably would be less painful for her if some random officer simply executed her instead, as implied by Hyzenthlay.
This is beautiful
I want this on poster or something so I can hang it my wall. I want to see an actual tv teleshopping thing for this even more.
Thank you

I was confused why Nettle didn't escape with the other rabbits when she was standing right outside the exit where they were escaping. She might have not thought their plan would not succeed, and if she ran away with bigwig and the does and got caught, she would probably have been killed.
I'm rather confused too. As Inlé-roo points out, she would probably have been killed any way. I can't blame Hyzenthlay for leaving her behind; several of the Sandleford gangs wanted to leave Strawberry behind too, in all adaptations. But, unlike Strawberry, Nettle didn't make a desperate plea for a second chance. This is what confuses me.
I need to watch this again...
she would probably have been killed.
Sadly she's probably dead. In the second episode Hyzenthlay said Holly they destroy everyone who felt behind. And at the chimney it was a really honest moment when Nettle said She didn't gave any name to them. With that was another great moment when Hyzen discovered the truth about Nettle she wasn't angry more like really sad and disappointed because she know that Nettle gonna die. Back to the chimney escape scene, she decided to left her because she lied in front of her. That's a sad scene but honest, no one needs a lier. 
I like her character (aka Nelthilta) but in the miniseries I feel her more understandable rather in the book. She made some bad choices but deep inside shes a good rabbit. Just wanted keep safety to her friends and family instead in the book she just shows off...
Kinda sad for Nettle though. It kinda seemed like she was remorseful, but she did lie again...