Gears of War 3 missing from Owned Games Library and Game Pass

I own a digital copy of Gears of War 3, and also had it under the Game Pass list till about sometime on 1st July. Had it installed on the 1st to begin playing on the 2nd, but it then came up saying I didn't own the game, and asking to buy it or insert CD.
I've played the game before and completed it, and wanted to play co-op with a friend who recently signed up for Game Pass Ultinate. For him, it said he needs to renew his subscription, when its valid till summer next year. Other game pass games seem to load
up fine.

Posted on reddit and it looks like several others sre facing the same problem - https://www.reddit.com/r/xboxone/comments/hjx3xu/gears_of_war_3_missing/

Tried chatting with someone here and they told me to reach out to Epic games and then just disconnected. This is clearly a microsoft problem, and not a game dev problem. Its a truly disconcerting thing to see a game you not only own a copy of, but also have
as a part of your subscription, just up and disappear without any notification, and are now asked to pay for it again.

UPDATE:

1. Just checked and the game still doesn't appear in the Game Pass list or my library of All owned games. However, on the store page, it now says "Install" instead of "See Price", but also says I can play with game pass or buy to own it, when I already do
own it.

Installed the game again, and it loads. But still doesn't show up, under "All owned games" in my Xbox "Full library".

2. Heard back from Epic Games; they said it's a Microsoft problem, which is obvious, but good to have confirmation.

:)