What's your question? Ask

You can try misting the fronds and slowly peeling from the wall.

This is normal. This will become a protective cap around the base of the plant. This article will offer information on the care of these: https://www.gardeningknowhow.com/ornamental/foliage/staghorn-fern/staghorn-fern-information.htm

There should still be some type of media for it to grow on so that it can harvest nutrients that get stuck to it. It is likely that there is a liner of some type but it could be hidden by the "cap" that forms at the base of the plant.

This article will give you more information on the care of these plants: https://www.gardeningknowhow.com/ornamental/foliage/staghorn-fern/staghorn-fern-information.htm

Many plants are very sensitive to copper. Being in direct contact will kill some completely. In fact, that is an old remedy for some stubborn trees. If you can find copper nails anymore, you can drive them into the tree in several locations to kill it off completely.

I recommend anything outside of copper... even aluminum, which I don't recommend for a long term solution. Plant ties are very inexpensive and can be purchased online even. It is best to avoid copper, altogether. It will lead to a dead plant.

What is your climate zone? This tree only has a limited range. Are there others in the area that are flowering as they should?

If this tree is in the correct climate, and the soil has been amended and tested to be healthy and fertile, then it could be that the tree is, simply, not old enough to flower properly yet.

If the soil is questionable, then I would say that there is too much nitrogen, or a lack of phosphorus and potassium. Adding phosphorus and potassium would correct this issue.

This article will help: https://www.gardeningknowhow.com/ornamental/trees/sumac/sumac-tree-info.htm

If the plant's base, where the frond branches meet, is black, then the plant is dead. A common staghorn fern that is kept too wet is vulnerable to fungal infection, most often rhizoctonia. The infection causes black spots to develop on the thick, rounded fronds that overlap and hold onto the fern's growing surface. The fungus can spread rapidly into the growing point of the plant, killing it. Reducing water at the first sign of black spots can help control the fungus, and the infection can be treated with a fungicide. Fungicides are available at home and garden centers.