I am sorry, but I do not know a thing about palms. I do know, though, how sad it is to lose a tree. I hope you can save it.

How cold did it get and for how long? Foxtail ferns are not very cold tolerant and can be damaged at temps below freezing. Although I have no personal experience to confirm, most sources state recovering from frost/cold damage is iffy. And slow.

Contact your local extension service. They're usually very responsive and they'll know a lot about your climate, including recent cold spells. And, they are professionals, not randos on the internet.

What is a local extension service?

Every state has an extension service sponsored by their land grant university. There are usually offices located in every county. They were formed early last century to support farmers in all things agricultural but have since broadened to include all home gardeners. They hold classes and lectures, issue publications, offer plant ID and pathology information and answer questions. They used to provide soil testing as well but the demand outgrew the ability. They are a font of local gardening info.

Yup, I looked it up and we got one! Central Sierra Co-op. Thank you!

The Master Gardener program is also associated with the extension service. And they often provide staffing for the county offices. So not really professionals but instead semi-trained volunteers :-))

My extension service in Maine provides soil and disease testing. Both are quite affordable. They triage questions, so for ailing trees, the advice is usually from a professional arborist/tree disease specialist. If you have a question about what native plants will work in your yard, you might get a response from a master gardener, not a professional.

I live in Florida as well, and suspect that your palm has a fungal disease known as ganoderma. I've lost multiple palms to the disease. Older leaves die off, and new growth is pale and stunted. There is no cure or treatment. Diseased palms need to be carefully removed, as the disease is easily spread (don't mulch or chip the tree). Any tools that come in contact with the tree need to be disinfected before being used again. A good tree guy or an experienced landscaper could confirm the diagnosis readily.