IMHO the SCCM sounds like a loose cannon, should be busted back to a no2 or whatever and retrained in SEP and CRM.
I would disagree...she should be
terminated, forthwith.
Loose cannons are not appreciated, nor desired, in the cabin.
Full stop.
PS.
I've seen a few of these 'loose cannons' in several airlines, and they were
all shown the door by the HR (and CC department), with very good reason.
Expunged, pronto.