I was doing the same .
I payed for 1 month subscription on boosteroid where i could play bg3 from steam.
And i have steam deck where i play it to.
For me this method was working.
I had the same issues when i quited the game from the actual playing. And dont waited until both in the game and steam cloud saves was in synchron.
Sometimes i lost the saves .
Also you need to enable cross save i think in option menu.
Last edited by ZOZO1006; 20/01/23 09:49 AM.