Sorry to catch you off guard but, there is no 'interface to upload' that you speak of in my centos7 version 2.7.0 .
There use to be one in there a few versions ago. Manual uploading worked as of 2.6.9. Interface downloading is still there. Perhaps a missed bug in last version.
The option I used was the only available one to me, and 'spoofing' that to make it work. If you have a method, I'm all ears 'cause my mysql's are not restoring correctly either. Corrupted in some way that I can not log in even with newly generated passwords or the old ones. Even went back to earlier back-up that were known good from the last update crash.
I keep 2 months+ worth of DB back-ups off server.
A lot of good that does me if I can't upload and restore them 'and have them work'. Better off phpmyadmin manually backup the DB. And it looks like I should have been doing that over relying on the webuzo datadump backup.
I'm guessing you changed the 'format' of the DATA-DUMP-BACKUP without making any backwards compatibility considerations or those are just in major error.
Whatever the case, if you don't have a fix for this as-is, I'm going to have to remake all 11 of my personal webs that have taken me years to build-out.
But I don't think I want anything to do with your back-up again. But I would like to have my sites restored.
then....
I think rsync with cron for local and remote server mounted backups make more sense than this aggravation.