Corelating to a MessageEvent after a Event Based Gateway

Hi I have a model structure like this.


This is inside a sub-process of a process. This sub-process is for different shops in an order which is controlled by the parent process.

To corelate to a messageEvent I need the messageEvent to hold the shopId like this.


However, since the flow is not reached the messagereceived event, and stuck at eventBasedGateway, the customShopId is not resolved. (Assumption)

How do I solve this?