I think I'd back off on the supplements too for a bit and just find a good kibble that she'll eat (if she needs the slippery elm for a bit keep adding that).
Kind of like an allergy elimination diet. Get her on the minimal nutritious food and only add the supplements one at a time to see how she does on them.
MACH3 Bretta Lee Wildhaus MXG MJG MXF MFB TQX HIT CGC TC
Glory B Wildhaus AX, AXJ, XF
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