Just keeping safe is good enough… At least you have backups which is something we always bang on about here, as it is few people have them so if things go a bit pear shaped whilst the cleaning is in progress it can take longer to recover.
In this case it looks as though Combofix managed to delete the bad copy of explorer but for some reason failed to copy the good copy over. It was recoverable but would have taken three or four extra posts to get it…