Rafiki, it is nice of you to wish you could help interpret this.
It took a lot of reading, but think I have more or less managed to figure it out. (any corrections are welcome) It is sort of like doing a crossword puzzle, but the educational clinical resources online are amazing.
The extremely high bile acids suggest cholestasis, which is an obstruction in the one of the systems that remove the bile acid from the blood and recycle it properly. It sounds like this can be caused by an end stage hepatic shunt, a physical obstruction or a chemical dysfunction. In the case of a physical obstruction (like a tumor) the liver chemicals GGT and ALP are usually higher than normal. For Moggie these chemicals were high but within the normal range, which may mean it was more likely a chemical dysfunction. And FIP affecting the liver can sometimes cause high bile acids.
High bilirubin may suggest inadequate liver function and can also be caused by FIP due to the cats inability to clear out red blood cells that have broken down. As far as I can understand, his other liver & kidney function chemicals were not ideal but were within normal range.
I think very high blood protein and globulin suggests his body was fighting an infection. Low albumin in itself can be liver dysfunction, or malnutrition. The very low A/G ratio is one of the most common markers of FIP, but can also point to lymphoma and some other less likely things. I don’t think this part of his blood chemistry is normally associated with a hepatic shunt, and he also did not have other symptoms of this like drooling or changes in behavior after eating (except maybe the compulsive burying)? On the other hand, I am not sure why the vet couldn’t feel the rim of his liver when he reached under his rib cage. If he had an unusually small liver, I am not sure if that might be caused by end stage FIP, as this usually is said to cause inflammation?
The Keratic precipitates (the spots in his eyes) are probably a big clue as they are frequently associated with FIP, and (I think?) much more rarely associated with other health problems. This is caused by collections of inflammatory cells.
I feel I have enough information to be able to let it rest guessing this was FIP, or maybe a lymphoma, though I will never know for sure. The Dr interpreting his blood results may have been a bit thrown off by Moggies age. The paper work is incorrect and says Moggie was 8.5 years old when he was 8 and a 1/2 months. Cats that are 8 months old are a lot more likely to develop FIP than a cat that is 8 years.
Thanks for all the information provided here and to those who provided support. It helped...
(edited to remove what was probably incorrect information)