The same is happening to me. Once the validation and uploading were successful, and after the rejection, I changed my App and archived for validation, and this happened to me.

I found that replacing the executable with an older version of it solved the problem. Up-versioning of Xcode (now I am using Version 11.3.1) may also work.

Thank you for your post. I did as you suggested, and my own executable worked fine, successfully creating a file in the container directory.