Kevin,
As I'm a bit lost with current status, could you clarify some points:
- can you access system console or not?
- in case you can, did you check if Chad's account exists in both /etc/passwd ans /etc/shadow I'm pretty sure your Linux guru checked if he got access but it's worth to ask.
- if account exists in LDAP:
PAM may prevent to change password from Linux CLI
password can still be changed using LDAP command from another machine.
In order to check this, you can search for uid=chad using ldap command line
ldapsearch -x -h your.ldap.server -b "dc=host,dc=domain,dc=com" uid=chad