After importing the images into a new project, are the images placed properly in the Map view? is it possible that some of the images are quite far away?
Regarding the pivoting images, you can try to disable every second/third image. You can try to import only part of your images, not all of them and then adding the groups. I suppose you will need to use more control points and using the GCPs would be very helpful there.
But as the capturing is not done in a proper way, it can be hard to achieve the wanted results.