No, that isn’t the problem. The problem was hidden in your conversion log. Some process is blocking the converted file while MP4Box is working on it. Likely an antivirus or something else monitoring that folder is putting a read lock on the file. MP4Box fails to rename the file because of the lock and subsequently MCEBuddy can’t find the file it was expecting and it fails the conversion. We’ve seen this before, put an exclusion for your temp working folder into your antivirus or disable other software which may be monitoring your temp folder. See these lines from your logs
2017-07-27T18:56:34 MCEBuddy.AppWrapper.MP4Box → Error renaming file out_Celebrity Name Game (2014) - S03E62 - Episode 62.mp4 to C:\Temp\DVRConv\working0\Celebrity Name Game (2014) - S03E62 - Episode 62.mp4
ERROR> 2017-07-27T18:56:38 MCEBuddy.Engine.ConversionJob → Converted file has been renamed or deleted by custom command → C:\Temp\DVRConv\working0\Celebrity Name Game (2014) - S03E62 - Episode 62.mp4