Keep in mind, not all the work orders created in the backend will be pushed to the user's devices.
Only those orders with a certain criteria will be pushed. That is possibly the reason that you do not get any pushes, the problem is not the on the service events.
Please check the exchange object settings in the config panel, SWM62_WORK_ORDER_PUSH, change detection condition filter. You need to set the criteria I mentioned in here. Let me know what you find.