I personally think it’s bullshit to say Ahsoka and/or Ezra survived because even though “I’m no Jedi” for the former, Ezra IS a Jedi. And that kind of destroys the idea that Luke is the Last Jedi. But I think it was bold enough already to kill two (one for sure) of the main characters.
Well we know Ezra is alive (based on Filoni statements, also so is Thrawn) but no idea what state he’s in. I’m imagining he’s sort of been out of commission in some way otherwise he’d have tried to make it back himself.
I definitely think there needs to be some explanation of what Ashoka was up to (and why, I suppose, Yoda felt they couldn’t rely on her).