Hy
next time (hopefully never) if HUD is missing, take HUD control unit fuse on LEFT side position F4 5A fuse out for few minutes. Just open LEFT door and remove dashboard cover, there is only one row of fuses. Usually this helps ;)
best regards
Edit: I mixed sides, correct location is LEFT side
Hy
most probably they will say- yes there has to be a fuse, BUT in reality there is no fuse, so all is good with Your car. Even dealer wiring diagram is wrong, been there, done that ;) No taycan has a fuse there.