That's awesome, Ryan! Your applescript-fu is way stronger than mine. I didn't know applescript can do that. This knowledge will change my life forever.
I expanded the workflow to take the search parameter from Alfred, in case anyone else wants it to work that way:
https://www.dropbox.com/s/bknzfwopa6u0687/Find%20in%20Dashlane.alfredworkflow?dl=0