She can't be expelled either. Short of being arrested for a specific crime, this would be up to the voters in California to go through a recall process, and I'm not sure if I hat applies to Congressional seats there.
I think she can be expelled from the Congress (which would require an act of Congress), but not the Speakership? I know that sounds odd, but being a Member of Congress is not a requirement to be Speaker (although there has never been a Speaker who was
not elected from the House membership that I know of).
As for a "recall elections" for Congresscritters, I don't think that's allowed. It's like Term Limits...no requirement beyond the Election is permitted.