Hi goldie11,

Ficus nitida provide dense shade but as you are aware, are easily damaged by cold temperatures. Because the symptoms you describe appeared before this year's freeze you could have some other issue besides the frost damage.

Have you used any herbicides near this tree? Have you done any remodeling or excavating near the tree like adding a patio or sidewalk? You may need to do a little detective work to see if something seems suspicious.

For now just provide good deep irrigation and don't apply any more fertilizer. Too much can cause salt burn which causes brown, dry edges on leaves. Don't water too often -
a good soaking at the drip line once every 10 days to 2 weeks in summer is ideal.

The holes you see on the trunk are most likely caused by sapsuckers. They drill or peck regularly spaced holes around a branch or trunk usually in straight rows or lines. The holes from borer damage will be irregularly spaced and are often accompanied by 'frass', a sawdust-like material that's basically digested wood.

I hope this helps.

Here's a great resource from the U of A. Besides disease symptoms, it has a section on cultural problems like nutrient issues and salt burn.

Here is a link that might be useful: Diseases of Urban Plants in Arizona