most if that sounds very familiar. It is fortunate you are able to consume lactose free items. Personally no snd have not found any (stress any - spent countless $$ attempting) type of protein addition that my system will tolerate. For myself, it seems SIBO is simply the outcome of a digestive system that just does not work.
Literally wasting away from malnutrition and all the others issues I carry suck beyond descriptive words and there is no end to the experience other than the inevitable for each of us.