In order for the update to take effect it needs a restart or confirmation that the update is completed successfully right so I think it’s not because of the update.
Your GPU died on its own.
GPU driver updates through windows updates don’t require restarts, it just downloads and starts installing on its own in the background, and the screen will go off and come back on normally.
Still unlikely that an update would kill the card though. The RMA should go through and he should probably get a replacement.