I don't know how much of the information will be made available or when, but just like the automotive industry, patentrs were obtrained and certain things were trademarked and until the patents have been out long enough, no information has to be made available. I rremember back in 2000 I got a new Chevrolet service truck and for several oil changes, had to go back to the dealer for the filter as they proclaimed some type of change and the previous model years filter would cause issues. If you built something and patented it, you would have a certain number of years before it could be copied. There is no easy solution except to make friends with the dealer techs and cross friendships and hope they will give you the information you need. All of us have been stuck with the lack of info and know the problem.
As to repairs coming back at you if they crap out and cause injury, one has to play that one by circumstance. Dealer techs, or those working for someone else are usually covered by trhe liability insurance, but that doesn't mean you can't be sued for ignorance in some states and be forced to defend yourself. No easy answers, or no air tight answers. Use extreme caution.