I am so sorry for your news
I know your fears and I didn't want to be in the same situation with my Vinnie. He did not have the same thing, but we could have ended up in the same place.
I will be thinking of you both...
We had two with orange poop after vetting. Chase had a multiple extraction during his dental and Jake had abdominal surgery. I have no idea why they went soft and orange. In a week or two I got them firmed up and back to their original color with kao-pec from the vet. It is not the stuff with the salicylate. It is kaolin and pectin. We have really god luck with it and have been using it for years.
We like this brand best: http://www.jefferspet.com/ssc/product.asp?...p;pf_id=0027459
Good luck with Wren