I am having the same issue with the screenshot and crash feedback in ASC. I have not received any screenshot or crash webhook events since August 5th. The rest of the event triggers seem to be more or less working as expected. The crash and screenshot feedback is populating in ASC/Xcode and I can see the feedback by hitting respective APIs betaFeedbackScreenshotSubmissions and betaFeedbackCrashSubmissions, but the web hooks show nothing being sent in nearly a week. I can confirm that the testing group does have tester feedback turned on as well and that has not changed.

Same issue here. Seems to be present in 26.1 and 26.2