Yes. I am using the Tagus and running two 1920 x 1200 monitors. When in this mode I have the Book display off and closed. Works great.
Also, from what I have seen in other threads, it seems like the 1920 x 1200 or 1048 displays on the DisplayLink are more stable than the 4K on the Book Dock.
However, occasionally, I have seen is the same problem I have heard about the Surface Dock for the Book, where it never finds the DisplayLink. I have to start it up without the Targus plugged in and then plug it in. I suspect this might be a USB problem of some sort. I had an external SSD plugged into one of the Book's USB ports and the DisplayLink plugged into another. Was using the tablet separately the night before and turned it off when done. When I plugged it into the keyboard and turned on the power, it did not even recognize the SSD. Popped the top, restarted it, waited until I could log in and re-docked the top. Then, everything started working.