Here is what I know/do:
DEBUG_INFORMATION_FORMAT should be set to dwarf-with-dsym for all configurations.
This could also be a timing issue, make sure the Fabric run script build phase is the last build phase and no other scripts have moved the dSYM from the location Xcode generated it. Unable to process myapp.app.dSYM at path /Users/no-one/Library/Developer/Xcode/DerivedData/myapp-ahatoktzxteqbcaohqnktdtfczxr/Build/Products/Debug-appletvos/myapp.app.dSYM
Make sure your project build settings are generating a dSYM file.
Go into your target's Build Settings and then type in DEBUG_INFORMATION_FORMAT
into the Search Bar that appears in the top right.
And you can choose "Dwarf With Dsym" from the pop-up menu.