Architect Flow Deployment Validation Failure in EU-West BYOC

I can’t seem to figure out why the deployment of our updated Virtual Agent flow is failing validation within the EU-West BYOC environment. The flow version is v5.1, and the change involves a simple addition of a new Data Action to capture custom session attributes. However, the platform returns a generic validation error that does not specify which node is causing the issue.

The error message provided in the console is as follows:

Validation Failed: Invalid configuration detected in flow structure. Please review node dependencies and output mappings.
Error Code: 400 BAD REQUEST

We have verified that all referenced data actions exist and are active. The previous version of the flow deployed without issue. This blockage is preventing us from testing the new attribute capture logic required for our upcoming reporting cycle.

Is there a known issue with Data Action mapping validations in the current EU-West release? We need to understand if this is a syntax error in our node configuration or a platform-side validation bug. Any guidance on how to isolate the specific failing node without manual node-by-node inspection would be appreciated.