Clarification on certificate bundle vs certificate chain
Normally a certificate bundle refers to a bundle of Certificate Authority certificates, like this one https://curl.se/ca/cacert.pem included with cURL.
A certificate chain usually means a server certificate and its intermediary certificate chain, all included in the same file or not, depending what options your software offers to configure this.
For example, the Apache HTTP server can be configured with different files for the server certificate and certificate chain.
A certificate chain sometimes can include the matching private key for the leaf certificate too.
If your appliance only needs to verify the SSL certificate of your AD/LDAP server, you only need to provide the CA cert and if your AD/LDAP cert is self-signed then the server certificate itself without the private key.