My comment in the patch is not clear.
voice.raw file is located in patch directory in your computer.
The axoloti patcher synchronises with git and that's how you can retrieve the file from your computer. You can see it here : https://github.com/axoloti/axoloti-contrib/tree/1.0.12/patches/gao
I don't think there is a way to upload files automatically to the SD card.
So all you have to do is take the voice.raw file and upload it to the SD card.
To do this use the file manager of the patcher and upload the file in the patch directory "sampler.rockafella".
If you can't find the file on your computer, you can retrieve it by following the git link above.
I hope that this time I am clear !