I'm seeing this same issue, two parallel Jenkins jobs that run xcodebuild and in one CodeSign usually fails with the same output as above. Running the jobs individually never fails. Not using temporary keychains just the login keychain. Not using fastlane either.
This looks like some kind of concurrency bug in CodeSign?
Anyone have any solution or constructive suggestions?
Since there's no crash there's obviously no crash log. Nor is there any console logging from CodeSign