Terri, I have a breed that has some liver enzyme issues. I have used both Denosyl and Denamarin. Here are some links with more information.
Last year, I had a dog with multiple health issues who developed bacterial hepatitis. She was given the denamarin with an antibiotic and her liver enzymes dropped 800-1000 points in one month (still elevated). This was a dramatic improvement as two liver enzymes were around 2000. She was given an NSAID to treat suspected bladder cancer and sadly, her liver was so damaged at this point the NSAID threw her into kidney failure and she passed. My dog had multiple severe health issues, beyond what you are seeing with your dog. I do understand wanting to use caution with medications and liver problems.
I also used denosyl for two Scotties and had success lowering the AlkPhos liver enzyme (tends to be elevated in this breed). A 6 month course pulled values from 1,200 and 1,500 to the 600 and 800 level. One dog was also tested (negative) for Cushings.
I've had success with the supplements and would not hesitate to use them in the future again. Good luck to Lucy.
Jenn (Mandy252), I also wanted to wish you luck with your doggie and vestibular. We are going through this with our 14-year-old. He was doing great, but had a mild relapse last week. We are concerned, and I just wanted to offer you a hug.