CAMID migration | Invalid credentials

Hi All,
I am working on one scenario in which customer domain name is changing. They have been using Cognos from long time now and their Active directory is getting upgrading and they are changing the domain name.
Cognos Version is Cognos 10.2.1.
We migrating Active Directory from Domain A to Domain B

Domain A : NAME-OR

Domain B : NAME.ABC.CN

As per my understanding once we change the domain name, the CAMID associated with the users will be changed in the Content store so the existing users will loose their My Folders content.
As domain name is changing the base distinguished name associated will also change and obviously CAMID will change. Currently after configuring the new active directory, existing users are also not able to login and get message “Invalid Credentials” when trying to login.
I have going through the Proven practise document on “Handling Security Changes”.
How can we handle these CAMID changes so that user login will be seam less.
We are also planning to use “IBM Cognos BI Security Replication Application”, has any one used it and please let me know your inputs surrounding this use case.
Note: We are not planning to use tools from Motio and BSP because of some restrictions.