He might not know the state of her heart, but it seems unlikely he didn’t know she’s not Catholic.
She could have accepted Christ in the middle of all this chaos, You and I probably “THINK NOT” BUT thats why scripture says.... Who knows the thoughts of a man but the spirit of the man?
[10] But God hath revealed them unto us by his Spirit: for the Spirit searcheth all things, yea, the deep things of God. [11] For what man knoweth the things of a man, save the spirit of man which is in him? even so the things of God knoweth no man, but the Spirit of God.
SEE I am a Follower of Christ. IF I right now am living LIke the Devil and went up and had communion that day, Damnation would be upon ME. The Priest does not know the state of my heart. Thats why it is all MY responsiblity to know wheather or not I can go up and have Communion.