Use the ![CDATA[ ... ]] wrapper to make sure that the & symbol is interpreted correctly.
and below is the link for related documentation!
http://docs.splunk.com/Documentation/Splunk/7.1.1/Viz/DrilldownLinkToDashboard,Use the wrapper to make sure that the & symbol is interpreted correctly.
Here is the related documentation
I am using 3 different browsers on 3 different monitors atm. Looks like its dependent on both the query and the browser should have the open-in-new-tab option enabled too. In Firefox, I had the target="_blank" which would open on another window. But enabling "open in new tab" and ctrl+clicking solved the problem in firefox and in case of other browser , opening in window is fine as well. Thanks for the help @poete.