Q.Norfolk Island Pine
I have an eight year old Norfolk Island Pine with five smaller pines growing from her. Recently, she has developed what I think is mold or mildew or I’m really not sure what…but the drainage water after watering her is stinky and some of her branches are very dark brown, not like when overwatering..Is there a product or home remedy I can do to heal this tree??? It is a very special tree to me. I live in Tempe, AZ and cannot bring her in the house, but this has never happened before.

This article will help with repotting.
https://www.gardeningknowhow.com/houseplants/norfolk-pine/norfolk-island-pine-repotting.htm
Watering issues and lack of humidity are common issues with an indoor Norfolk Pine.
This article will help you with care.
https://www.gardeningknowhow.com/houseplants/norfolk-pine/norfolk-dropping-branches.htm