Hi @glam02,
There is a really neat Galaxy Admin utility called gxadmin which can help you out. It contains a bunch of querys and scripts that can look at jobs, fail jobs manually etc.
You can get it from: https://github.com/usegalaxy-eu/gxadmin
The particular query you want to run is: gxadmin mutate fail-job <job_id> where <job_id> is the job number of the stalled jobs in your database.
There is a little bit of setup required, mostly so that gxadmin knows how to talk to your database.
I hope this helps.
Simon.