Hi All,
   I am new to Ovirt. I am hitting the exact same error while trying a new install in a nested virtualization setup on esxi 6.5. 
I am following this tutorial as well. Have three nodes on esxi with dual networks & passwordless ssh enabled.
https://www.ovirt.org/blog/2017/04/up-and-running-with-ovirt-4.1-and-gluster-storage/

Node install goes through without issue. Run into this error when i hit deploy. 

TASK [Run a shell script] ******************************************************
fatal: [ovirt3]: FAILED! => {"failed": true, "msg": "The conditional check 'result.rc != 0' failed. The error was: error while evaluating conditional (result.rc != 0): 'dict object' has no attribute 'rc'"}
fatal: [ovirt1]: FAILED! => {"failed": true, "msg": "The conditional check 'result.rc != 0' failed. The error was: error while evaluating conditional (result.rc != 0): 'dict object' has no attribute 'rc'"}
fatal: [ovirt2]: FAILED! => {"failed": true, "msg": "The conditional check 'result.rc != 0' failed. The error was: error while evaluating conditional (result.rc != 0): 'dict object' has no attribute 'rc'"}
to retry, use: --limit @/tmp/tmpbDBjAt/run-script.retry


@Simone Marchioni were you able to find a solution ???. 

Thanks
hk