What is the value of Station AETitle for your work list items? ((0040,0001) Scheduled Station AE Title)
What criteria is the modality using for querying the work list?
You can create your worklist item with an assigned Scheduled Station AE Titlte but ultimately you have to make sure that your modality is actually filtering by that criteria when it queries the worklist. It is perfectly legal for a modality to retrieve all worklist items even if they have different Scheduled Stations, you have to explicitly add the criteria to the query.
Most modalities query by date range and by modality (CT, CR, and so on) you should be able to configure your modality for only retrieving items that match a given Scheduled Station AE Title.
If you can't do this (some modalities lack this, I've seen a few), you will have to coerce the incoming MWL c-find request by using a mwl-cfindrq.xsl on ...server/default/conf/dcm4chee-ae/, All this assuming that the worklist item created by the orm message actually has a Scheduled Stations AE. (It should, it is a mandatory field, so it needs to have some value, so make sure that it is the correct CLIENT1 or CLIENT2 ones)