I am intrigued, call it nosey, but why not just go to the garage? I can’t help but think that the handover of a scooter is very different to that of a car? If the garage is happy to do a handover at home, I wonder why it can not be done. I bet it will be to do with insurance. I hope it is resolved for you without any more grief and time delays.
It is not just Mobility Scooters you can order and have delivery from home it is WAV cars MPV that you can do this so a one for one but not us?