How do you insert a value from a WebApp into a module

[ManOfLeisure77]

I would like to display, for example, a list of all sessions for a particular venue in the venue detail layout. I wanted to display the sessions based on their classification. What I would like to do is replace the itemID parameter with a value from that web app. For example:

In the following: {module_webapps,22019,c,73908}

I want to replace "73908" with something like {module_webapps,22019,c,itemID="{tag_VenueClassificationID}}" VenueClassificationID is a custom field from that WebApp. However, I don't know the appropriate way to do/write this.

Any help is appreciated. Thanks!