As long as you did not suggest naranon while 'officially' sharing at alanon, its ok. you can take someone aside after a meeting and suggest a book you read, another 12 step program, or whatever- as long as it isn't part of your 'share' during the meeting. The way I got into NA many years ago was that I had been going to AA, and shared that I had relapsed on drugs. An NA member took me aside after the AA meeting and told me she also attends NA and I might be more comfortable there. I was, and I am grateful she did that. And good for your for letting the facility know about naranon.
BTW, how wonderful that your sister is in treatment!!