But you can check the Log Files each time someone does a reload on qvf/qvw.
In Log file you can see the NT NAME of the user who refreshed it & also Time Stamp will be available.
This is not just limited to one QVD. If you have 1 QVD loaded then it will show for 1. If more than 1 is loaded then it will generate full load script log.
Location for Log Folder on Sense Desktop: C:\Qlik\Sense\Log folder ( if you've installed sense in C Drive.)
For Server: C:\ProgramData\Qlik\Sense\Log\Script
And I'm not sure about 2nd question.