It is too late if her ears are frostbitten. Floppy is not good unless they are a floppy eared breed. Swollen, warm to the touch not very good signs. They may or may not turn dark.
I had surprise kids born in the cold, the mom decided to be stupid and left the barn. I checked on her she was there, an hour later I go to check on her again and she was out in the cold and and had triplets. I dried them off well but for their ears it was too late.
They never got any darker as their ears inside were dark already, they got droopy, then they did get hard after a while, then they had cuts across them, I guess separating the dead from the alive tissue, the area eventually fell off. The entire process took a few weeks.
They are otherwise healthy just different looking
I did get a goat baby from someone who had frostbitten hooves. Said he was stepped on by the mom, but he was limping on both front hooves and they would bleed. So I took him to the vet who said frostbite, not stepped on, keep the snow off him. That was a challenge, he ended up wearing girls thinsulate mittens on his hooves

it saved his feet/hooves and he was fine once he got older. Only his front hooves had been effected.
So as far as her feet are concerned keep them as warm and dry as possible.
This is why I hate cold weather babies, so much more work. My surprise this year kids are wearing little dog coats and the nights is has been -25 or so I have been bringing them in the house.
The wether, he is still cute with his weird ears
His sister: