Not sure if this would work for your company, but here is an idea:
1. Check in the MOM revision (e.g. get it off the engineering workbench)
2. Set up a dummy job using the MOM
3. Run your standard job traveller report on the dummy job
4. Once you have your job traveller, delete the dummy job and check out the revision to your engineering workbench again
It's a bit of a "cheat", but it will save lots of time, especially if this is just a one-off request. However, if they are wanting to run job travellers for items in the engineering workbench on a frequent basis, you will need to implement a more sophisticated solution. Seems very counterintuitive to want a job traveller for a MOM that is not finalised, but user requests never cease to amaze.