It seems that it would be better for full-delete api call to either return 404 Not Found in this case or return true (i.e. file doesn’t exist). Otherwise we need to implement file delete with an additional API call to check does file exist or not whenever full-delete responded with false (i.e. we don’t know if file already doesn’t exist or delete failed for some reason).
Just wanted to give you a quick update. Product has an update for this that isn’t yet in production. Once it is, you can expect to get a 404 response when the file in question can’t be found. I’ll reach back out here once the update is live.