Hi AK,
I realise this is probably not what you want to hear, but unless you are using a production version of DIRAC all bets are off.
I don't know why you are attempting to use a random commit, but as a first measure I would ask your admin to move the server (and pilot version) to a production version.
Otherwise, without access to the logs, I don't think there is anything you can do from a user perspective.
Checking there are no formatting issues and/or impossible conditions in the jdl might help, but as you say it's a hello world job, that seems unlikely.
Regards,
Daniela