California

When you say he was "still around in 2020," do you mean that he's not alive now?

As you note in your list, to be eligible, people have to be a CA resident on the date the payment is issued.

I don't see any indication that a person who filed a 2020 return can get a check even if they're dead now.

I'm also waiting for my $350.

p.s. I'll keep my fingers crossed for you, but I'm not sure you should have your hopes up.