The log file indicates there is already a QlikView server running on the machine. For reference the line in the log file is:
[0FE8:16E8][2015-04-09T12:45:09]i000: Evaluated install condition QlikViewServer11X64Sr1Sr2 to True
Also, I just checked the Release Notes and on page 17 it says Qlik Sense Server cannot be installed on a machine with QlikView Server:
Qlik Sense (server) cannot be installed if a Server of a previous version (QlikView 11.20 or earlier) is installed on the same computer. In that case you will have to uninstall before proceeding with the new installation.