Check Data Credentials: Edit the Gladior data source and ensure Data Credentials is set to Owner’s Credentials instead of Viewer’s Credentials. Scheduled email deliveries fail silently on community connectors if set to Viewer.
Pre-cache with “Extract Data”: Scheduled email rendering uses a headless browser with a strict timeout. If Gladior takes a few seconds to call the GBP API, the PDF snapshot gets captured before the data loads. Connecting through Looker Studio’s Extract Data connector pre-caches the numbers so the scheduled PDF never renders empty.
We ran into the exact same thing a while back and the credentials fix @srivilliamsai mentioned is almost certainly your culprit, switching to Owner’s Credentials made a huge difference for us with third-party connectors. The Extract Data approach is also worth doing alongside it, especially if your GBP connector has any lag pulling in the data. Hope that gets it sorted for you!