Appalling handling on Google’s end here. The duplicate issue part I can understand, but why should it take two reports of a critical vulnerability to take action? Surely when the first one comes through it’s something you jump on, fix and push out ASAP, not give delay to the point where a second user can come along, find the bug, and report it.
The refactor that’s mentioned towards the end of the article is great, but would you not just get a fix out there as soon as possible, then work on a good fix after that? For a company that claims to lead the way in bug bounty programs this is a pretty disappointing story.