Regarding the leaves:
I notice one of your photos shows leaves which are beginning to yellow. This perhaps is Verticillium Wilt, which is common in Redbuds. Redbud trees can become affected by a soil-borne fungus called “Verticillium dahlia” that causes a fatal disease known as verticillium wilt.

The fungus enters redbud and other host trees through the roots and spreads throughout the plant through water-conducting tissues, resulting in leaf wilting and a yellowing of the foliage known as chlorosis. Over time, branches die back until eventually, the entire tree dies.

There is no way to treat verticillium wilt in redbuds. The pathogen that causes verticillium wilt can survive in the soil for years, so avoid planting redbuds and other susceptible species in the same soil where the disease was known to recently affect trees.

The other disease that could be present is Dieback/Canker, which is the most destructive disease that attacks Redbud trees. It is first seen as a tree’s leaves wilt and turn brown. Often cankers can be seen on branches and twigs. The cankers can either be seen as visible cankers on the surface of the branches or as dark sunken areas with black centers.

The canker or dieback is also caused by a fungus (Botryosphaeria ribis) which attacks not only the redbud but more than fifty other types of trees and shrubs. The disease is spread throughout the tree, or from tree to tree, by splashing rain and winds that move the fungus from diseased areas to healthy parts of the tree. The fungus then enters the tree through wounds or dying branches. The fungus gradually spreads out within the tree’s vascular system slowly blocking the tree’s vascular system and inhibiting its ability to transport nutrients and water. The result is a gradual dieback of branches as the flow of nutrients and water is cut off.

There is no effective chemical control for the canker. If canker is identified in a tree, prune out and destroy dead branches and infested areas. Be sure to make pruning cuts at least 3 or 4 inches below the canker, so that the cut is into healthy viable wood. After every pruning cut, be sure to properly sanitize the pruning tools so that the fungus is not transferred to healthy parts of the tree.

Regarding the shedding of bark:
Shedding or peeling bark is a characteristic of the redbud tree, as well as the silver maple, sycamore, shagbark, birch, hickory and Scotch pine, according to Iowa State University Extension. As the redbud tree matures, the inner bark layer thickens, which results in the bark being pushed outward as the tree grows. Eventually, the outer layer of bark dies and cracks and peels, exposing the inner bark.

Redbud trees often lose their outer layer of bark as they get older and more mature. Once the outer layer falls off, inner layers of orange bark are revealed. Cold, dry weather often loosens bark and results in large amounts of bark being shed the following summer.

No control method is recommended for redbud trees that shed their bark. If the tree is healthy, losing bark causes no damage. Redbud trees that suffer an injury to their bark may suffer from reduced health and vigor.

The following articles may be of help to you:
https://extension.oregonstate.edu/gardening/techniques/how-recognize-signs-verticillium-wilt
https://plants.ces.ncsu.edu/plants/cercis-canadensis/
https://edis.ifas.ufl.edu/publication/ST145
https://hgic.clemson.edu/factsheet/redbud/

Engaging a Certified Arborist to do an on-site assessment may be helpful. I recommend a Certified Arborist because they must pass a test and must acquire continuing education. You can locate such individuals at http://www.treesaregood.org/findanarborist/findanarborist.aspx