Trouble with Library Sharing

[t0asterstrud3l]

Exactly what it says on the tin, but I've yet to find somebody with my exact problem. A friend and I have successfully linked our libraries via family-sharing, and his titles are showing up in my library with no issue. The only catch is that one of the games I want to borrow most, RDR2, isn't showing up in the tab. If I check his profile and library it says he owns it, but when I check my library it's the only game of his that didn't carry over. I'm unsure if this is a game-specific issue or something on one of our ends.

One of the most likely causes I've found is that he hasn't downloaded the software before, which may be tripping steam up on the validity of his ownership or something? But his copies of the Yakuza series show up in my library even though I'm pretty sure he's never downloaded and played them. Any input on what's going on is welcome because as much as I love Arthur Morgan, I'm not spending $60 on him.

[WarHeRo]

maybe some titles are not available for family share

[Cathulhu]

Red Dead Redemption 2 has third party DRM (Rockstar Social Club) and can not be shared.

[StickyPawz]

Don't you need a Rockstar account for RDR2?

Games requiring 3rd party accounts aren't able to family share.

[SpunkyJones]

Games that need 3rd party launchers are typically not available via family share, like RDR2

[ZanyScum]

https://steamcommunity.com/app/1174180/discussions/0/5913830210151138109/