Does the scooter have a current valid registration, plate and sticker for operation in California? Are you saying that you have someone who's wiling to legally ride it or take it on a carrier to the DMV or CHP location? Or are you trying to get them to go the scooter's current location? (they usually won't do that).
What happens when you attempt to run the VIN on the
transfer calculator?
There's lots of reasons for them to deny your request, and most of them are green with Benjamin Franklin or dead presidents on one side. California requires that past due registrations fees, penalties, and "use tax" to be paid in order to allow title transfer. Registering in another state prevents California from collecting this money.
If the registration is current, then you need to pay the transfer fees and use tax (same as the sales tax rate). This is money they want too.
It gets more complicated if the owner has lost the title, since duplicate title won't be issued until all the past due amounts are paid. If you have the title, then you can register it in another state, but if that state requires physical verification, then the current registration status matters.
You may have to have someone register it for you in California first, and failing that, in Nevada or Arizona, if you have the title and want to avoid paying any registration fees and the use tax. Or you could have someone put it in storage for you until you're ready to pick it up, but then you would have to get it registered somewhere outside of California because you'll have the additional registration fees and penalties added on to it, since you can't file it as non-operational status until you transfer the title.