I’m trying to migrate WhatsApp from iOS to GrapheneOS on a Pixel 10 Pro, following this post:

https://discuss.grapheneos.org/d/13124-whatsapp-how-i-restored-my-backup-ios-to-android-android-to-android

What I've done so far:

Migrated WhatsApp from iPhone to Android stock.
Confirmed that the chats were present on Android stock.
Created a local WhatsApp backup on Android stock.
Pulled the WhatsApp folder to my PC with ADB.
Installed GrapheneOS.
Created a secondary user profile which will be my daily.
Installed WhatsApp in that secondary profile.
Copied the backup into the secondary profile with ADB:

The active user is the secondary profile:
adb shell am get-current-user 10

The backup appears to be in the expected location:

/sdcard/Android/media/com.whatsapp/WhatsApp/Databases/msgstore.db.crypt14
/sdcard/Android/media/com.whatsapp/WhatsApp/Backups
/sdcard/Android/media/com.whatsapp/WhatsApp/Media

Then I installed WhatsApp but it does not offer to restore the local backup. After verifying my phone number and granting permissions, it goes straight to a new/empty chat list. I tried clearing WhatsApp storage, uninstalling/reinstalling WhatsApp, and opening it only to the welcome screen before continuing, but it still does not detect the local backup.

Is local restore from Android/media/com.whatsapp/WhatsApp/Databases/msgstore.db.crypt14 still expected to work on current WhatsApp/GrapheneOS? Or is Google Drive / official transfer now the only reliable method?

What can I do now? Any realiable method to migrate that is working at the moment? I've seen a few apps for this use case, however I don't trust them as a general rule of thumb, don't know if there is some "reputable" option.

I've been checking the forum and see various approachs, however I'm unsure wether they are still working or not anyway.

Thanks in advance!