MacBook Air not booting, Boot loader not available, Internet recovery not available
I think I had one such MacBook Air. It was permanently resolved by replacing the LCD assembly at AASP as the warranty was active - it did essentially qualify for DOA (wtf? - still do not know the possible answer to that)

Workaround was to get the system in the target mode (T at startup and connect with a Thunderbolt cable to some other Mac) and install the MacOS from a good source.
ASD may help to point the finger to the dead part in need of replacement.