Data Exchange: Check member in target application before mapping

Summary:
Data Exchange: Check if the member exists in target application before mapping.

Content (please ensure you mask any confidential information):

I'm looking for a way to avoid data load failure from FCCS to PBCS using Data Exchange. I need to check if the member exists in the target application (Planning & Budgeting app) and if not, map it to a dummy member. I already have a * to * catchall mapping, so cannot use that. Would appreciate any ideas.