I'm a big fan of feeding tubes and wouldn't hesitate to put one in, if the situation warranted it. In fact, I've had to resort to tubes on 3 separate occasions for 2 of my cats. There is just no way I could possibly have force fed them for as long as they needed it (3+ months average), and because food aversions can develop with force feeding, tubes bypass that possibility. Meal times actually became a bonding experience.
If you do go for a tube, offer food by mouth before each feeding. Most cats adapt very quickly to wearing a tube (surgical socks help keep them in place). The other thing that's really great about having the tube is that you can put certain meds and liver support supplements through them, avoiding the stress of pilling. This can also help speed up the liver's recovery.
Hopefully the latest blood work provides some answers for you.
"To close your eyes will not ease another's pain." ~ Chinese Proverb
“We must not refuse to see with our eyes what they must endure with their bodies.” ~ Gretchen Wyler