This Quaoar event actually has us inside the shadow path, barely inside the northern limit. The target star is magnitude 15.5, alt= 38 degrees. At 38 degrees, the star will be 0.15 magnitude dimmer than if it were at alt=66 degrees. So, figure 15.6 magnitude, and to look like a 13.5 mag star would require 6.9 times longer integration. So if 16x will show the star clearly, we'd need 16x times 6.9 = 111x. Close to the 128x setting in the Watec. Can we integrate that long and not have a total white out? Perhaps if the focal reducer were removed, we might? Worth a try.
Alt=38, due south