I chatted with Dev and there is no way to upload name prompts through the API.
Rather than reset passwords, the voice talent can sit on one phone in the org and dial into voicemail through *86. To record for a specific user, enter that user's extension when prompted and access the Options menu.
To make it easier, don't have PINs assigned to the users (though, that is something the user does from his/her profile, so there may be some who have assigned a PIN and you will have to get them to change it to something generic for the recording).
Not a great solution, but at least it's something that can be done.
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George Ganahl GCP (PureCloud), ICCE
Principal Technology Consultant
Genesys
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