Yes the backup is successful in cPanel, but it does not upload everything to Drive. you can see that in the log 5625.710 – it only uploads the 7th package.
Please can you update to latset version 2.16.7, reduce the split archive size to 50Mb and then do another backup?
If it still fails to complete, you will need to contact your host/server admin and have them check the PHP error log. It should contain the exact information on the problem you are having.