Why did you have to install Ansible? Bahmni installer will fetch and install required ansible version.
What machine are you using? CentOS7 has various distro. Can you try with barebone minimal distro?
As indicated in the other thread, check a similar thread that I linked.
You need to ensure that ansible can access and provision both the systems. In most cases, people tend to overlook that from the control machine ansible uses the mentioned user to ssh to the other machine and install softwares. So, before you proceed with Bahmni, check if you can do simple things on the remote machines. (like write a file on both machines). Check the other thread for pointers.