Notarized but Gatekeeper fails macOS 15 only?

Okay, I just pushed a release and notarized. Works great on my test laptop (macOS 26.2) and my test desktop (macOS 14.x)

But it seems to fail for a friend who's running macOS 15.

I've been using the same GitHub actions successfully for months.

How can notarization work for macOS 14 and 26, but not for macOS 15?

I think everything looks okay as far as the signing?

I've checked codesign -dvv

Executable=/Applications/Avogadro2.app/Contents/MacOS/Avogadro2
Identifier=cc.avogadro
Format=app bundle with Mach-O thin (arm64)
CodeDirectory v=20500 size=11607 flags=0x10000(runtime) hashes=352+7 location=embedded
Signature size=8986
Authority=Developer ID Application: Geoffrey Hutchison (…..)
Authority=Developer ID Certification Authority
Authority=Apple Root CA
Timestamp=Feb 5, 2026 at 8:47:21 PM
Info.plist entries=24
TeamIdentifier=…..
Runtime Version=15.5.0
Sealed Resources version=2 rules=13 files=3306
Internal requirements count=1 size=172

And from spctl -a -vv

/Applications/Avogadro2.app: accepted
source=Notarized Developer ID
origin=Developer ID Application: Geoffrey Hutchison (….)
Notarized but Gatekeeper fails macOS 15 only?
 
 
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