Here is just one idea for debugging, given the weirdness you reported. Can you try activating the Ansible virtual environment?
source /var/lib/awx/venv/ansible/bin/activate
Then with that activated, try ansible --version again, maybe pip show ansible. The theory I’m testing (which may or may not be true) is that when Ansible gets installed in 2 locations they can wind up fighting. We generally rely on the assumption that Ansible is actually not installed on the venv (only the packages).