well it is hard to say for sure from a video but it looks like it is very possible the rear mount is going or gone. Another test you can try is get a pry bar and crawl under the car. Pry on the mount to see if it seems to move exessively. WHen you are prying it you may even notice the rubber bushing part of it seperating from the metal part of the mount itself.
The front mount was changed in March. The dog bone was changed over the summer, but cracked again (I think due to the rear) so I am making the top dog bone with polyurthane and that will fix that. But the rear has to be done, am I right?