I would focus on the āupgrade ended abruptlyā if I was you.
If the installer does itās work, then you donāt get these mismatches between database and vardefs (unless your system is already broken to a point where itās hard to bring it back to coherence).
Please check those logs I said, what do you see there when the upgrade ends abruplty?
suitecrm.log
upgradeWizard.log
Your web server log (errors.log or php_errors.log)