$ snap info mir-kiosk-kodi
name: mir-kiosk-kodi
summary: Kodi packaged as an IoT GUI
publisher: Alan Griffiths (alangriffiths)
...
$ snap whoami
e-mail: alan.griffiths@canonical.com
$ snap download --revision=382 mir-kiosk-kodi
Fetching snap "mir-kiosk-kodi"
error: cannot download snap "mir-kiosk-kodi": Access by specifying a revision is not allowed for this Snap.
snap version
snap 2.56.2
snapd 2.56.2
series 16
ubuntu 22.04
kernel 5.15.0-43-generic
snap download does not go through snapd, therefore it does not use or know about your credentials or authentication. It counts as an anonymous download basically
You need to export a credentials file using snapcraft and then use that when calling snap download so it counts as an authenticated access and allows the revisioned download.