The August 19th update from Parks Canada is consistent with this; it indicates that
With the two Canadian Hydrographic survey launches, Gannet and Kinglett readied prior to arrival, the marine search began immediately with a side-scan sonar deployed from each launch. The side-scan sonar is towed from the stern of the launch vessel, offering an acoustic image of the sea floor. During surveys with the side-scan sonar, our team will systematically cover as much of the targeted area as possible.
It's a little frustrating that the update doesn't mention the exact location of the "targeted area," but it's clear that it's in Queen Maud Gulf, as they mention consulting ice charts of that area. I'm relieved to learn that this is indeed the area of their work, and that they're focusing on covering as wide of an area as possible in the available time; I'm certain that's the right approach. After all, readers will recall that, in the search for RMS Titanic, Bob Ballard's team and a rival French outfit were trolling the ocean back and forth in just such a manner; thanks to good luck (and perhaps some historical tips, or intuition), Ballard was the first to locate her.
As of August 29th, the Laurier seems to be retracing its route, which -- if indeed the launches did manage some means of operating independently -- could mean that it is returning to pick them up. Only time will tell.