Send Custom Params to Target using Target Extention 2 in Launch

Can someone tell me how to pass params to Target using the Launch extension? The experience is designed that after a person completes an onsite search, they will not longer see a CTA for search. The Search component does not cause a post back or page refresh. 

I have target loading on all pages and firing on page load. 

I am using the search custom event to set the search=true parameter via the Add Params to All Events action.

What is next? It seems like the param is not being set because subsequent pageviews still have the Search CTA.