I feel like you wrote the story of my life. You describe my symptoms so accurately. For me it has been going on since June 2018.
Here's a too-quick example of some logical thinking. It's known about the connection between 5-LOX and Leukotriene B4, and neutrophil activation.
Meanwhile, your PR3 antibodies activate neutrophils - which then go on to cause inflammatory damage.
So I'd thnk of trying an OTC 5-LOX inhibitor, which is Boswellia Serrata, aka Frankincense. That is safer than prescription corticosteroids, or powerful biologic anti-inflammatory drugs.
"Lyme test was negative and was sent to a rheumatologist"
What about tick borne co-infections? With the liver involvement, I'd think of Babesia.
"I know I’m not imagining this because physical symptoms keep me from believing that."
Yep, you are exactly correct.
I can delve into this with you if you respond. I see that it's been 6 weeks since you posted.
Think "mystery inflammatory condition".
There are three ways to proceed. (1) identify the cause and suppress that cause, or (2) simply attempt to interfere with the inflammatory biochemicals that arise when you get flares, and/or (3) try to identify the triggers that cause the flares.
"I have a lot more info I can add if requested"
Yep, that's very necessary. It's an interesting case :)
The type of doc for this is a rheumy, but you've seen how that goes when there is no ready answer. There's a small chance of getting to see a "Diagnostician" at a large medical complex - their aim is to solve mystery cases.