Were she actually celebrating Mass (handing out Communion is not the same as "giving" the sacraments. I'm sure that she was not able to "give" confession (that is, hear) any more than she was able to conduct "last rites" (wrong term, amiga).
Just because a nun violates church doctrine does not make incorrect actions any less incorrect.
I think that anyone may validly hear a confession in extremis if no priest is available.
She did it under the auspices of her archdiocese. Obedience is one of their vows..