California is out as they said they will not play there. I am with you and would have thought the stadium in San Diego where SDSU plays would have been an easy fix.
There must be a reason that the Raiders do not want to play in some of these larger stadiums or California, and I cannot pin point it.
And I also have heard that they could start the season on the road as it is another possibility. Yet, in Vegas, they keep talking about El Paso, Sam Boyd and San Antonio. These are the 3 they keep repeating. Also, that it does not have to be only one place, as they said they might play at different venues. I don't know why you would want to do that, as that would absolutely give you no advantage as it would not allow you to get used to the venue.
Honestly, I think the stadium will be done on time (July 31st), or at worst 1 month behind.