Only difference in /etc/yum.conf is:
Not present by default. I guess you added it to try to solve the problem.
Sorry for the confusion, the command would be using the transaction IDs you can get with yum history command, or all transactions with the wildcard:
yum history info *
This would just help if you spot some malformed command.
Python and packages versions are ok (I was suspecting a problem with the python version or some other required library).
Do you have custom repos?
yum repolist
Also note: