Poor Jenna 

. I think something more is going on here, I really do. Was a urinalysis ever done...? Those are very simple and it'd probably be good just to make sure things are okay there. And recent full blood chems...including kidney, liver etc..? Is her weight stable and appetite okay? 
On the dry eye, if a Schirmer test has never been - you might want to suggest it. Two of my kiddos had/have severe dry eye - and Pfeiffer was producing all kinds of eye-gunk still bc the eyes are so irritated. I would describe as different from the regular goop - it's not clear, it's not yellowish like some of the more normal goop, and it's not green - it's more like brown-rusty and it gets extremely hard -- it happens both at inner corners and on upper lid area. Since I started treating her about a month ago - omg, total change 

!!! 
When you say she's "chewing herself" - do you mean her paws mostly? Does she have allergies? If so, I've found both Apoquel and Atopica miraculous for allergies; and now there is the Cytopoint shot as well. 
Keep me posted on how the little one is doing!