Sexually perverted relatives

This is a serious issue and requires serious thought. I am specifically referring to homosexuality but shall refer to it as sexual perversion because I dont like the other word.

Now the issue is as follows. A person has known for about a year that one of his relatives female practices actively sexual perversion. He found out quite by accident but is absolutely certain that the issue is not mere rumour and that the person involved is actively practicing the sexual perversion. A year has elapsed. The person has not informed the relative that he knows her dirrty secret, only two other people know about this most shameful thing and they are the real brothers of the person who knows. Ie three brothers are aware of this fact and no1 else knows.

When the person found out his immediate reaction was to go and ask his imam about what he should do and was all geared up to ask but his shame got the better of him. The issue is so shameful that the person was even shy to go and mention such things to the imam to ask for advice about what he should do.

What do you think he should do?

At the moment, there is no major problem. The person who does this perversion is a strange relation (ghayr mahram female) and as the person does not speak beyond salaam with even female cousins he doesnt get any deep topics with the person. At the moment he gives salaam and leaves it there.

Should he confront the woman?
Should he inform her brothers and mother?
Should he just ignore it and leave her to it?