After much trial and error over the last few months, I have come to the psotive determination that the extra skin is the problem, Jennie, for whatever reason, is now unable to metablize that extra fat.
With the help of the IBD group I did try, with supplementation, to help her cope with the extra skin. The suggestion was to add lipase (and/or ox bile). I tried the lipase first. It gave her diarrhea, I am no longer using it.
I wasn't planning to update her progress until a full two weeks after the latest change but... I have stopped adding the extra fat entirely. 9 days since that change. She hasn't had a foul poop since. Not sure which way I will go if she should need help with constipation again, going forward. Neither SEB or psyllium work for her. I have increased her EYL by an extra half capsule a day. So she is getting 1/2 capsule at breakfast, 1/4 at supper and 1/4 at bedtime. Her lunch meal which is a small token meal, does not have any EYL.
Egg yolk lecithin, being a fat emulsifier, I figured it might help her cope, at least wiht the fat already in the meat.
So far I havne't seen evidence of constipation or hard dry stool..in fact the other evening she actually let me watch her poop, which she NEVER does. There was no straining, and the poop was a classic raw fed cat poop with no odor.
I never did put her back on turkey, but I may, in time. I am adding more Rad Cat to her diet for a little variety, since she is getting so much chicken now.
If she does start to have trouble with constipation, I may go to the coconut oil. the IBD group recommends MCT (medium chain triglycerides) claiming that the old study stating they are bad for cats was based on a flaw in the trials.
The other alternative is pumpkin, that's what she used to have years ago, before I went to raw, and, after raw, before I learned about adding skin for extra fat.