again just putting this out there in case it could help lead to some explanation for the low oxygen saturation etc
the lungs work by gas exchange between the gases in the little pockets of air in the lungs called alveoli and the haemoglobin in the red blood cells in the capillaries in the lung.
To get from one to the other, the gasses have to pass through the one cell thick membrane of the capillaries lining the alveoli
https://www.ncbi.nlm.nih.gov/books/nbk534789/figure/article-24501.image.f2/?report=objectonlyfibrin build up in these capillaries - even a v thin layer - as seen elsewhere in the body with bartonella and Babesia infections - i known to impair exchanges of gasses - so could be one explanation for impaired gas transfer - and this could be a possible explanation for low oxygen saturation and DLoc numbers ( also measures gas exchange i believe).
excess fibrin ( stained red) lining capillaries in bartonella infection - slide from Breitschwerdt et al
VIEW IMAGEagain - we cannot diagnose over the message forum - so just offering potential ideas to be followed up with formal investigations to confirm or dismiss - to hopefully help find out what is going on
when my fibrin was ait its worst with bart - my ESR was less than 1mm
this is unexpected in inflammatory/infectious conditions - and likely caused by the excess fibrin causing clotting to be suspended in the blood column - rather than increased ( ESR measures how much clotting products settle to the bottom of a tube of blood in 1hrs )
i am guessing they have measured ESR a few times so could be a potential indicator if this was also v low - given the other issues you are having.
if this is what's going on its likely very treatable