Broken Rear Radius Rods?

[DoubleA98391]

Hi everyone, this is my first post here but not my first visit. Usually I can find a post that will detail a problem I am having but I can't seem to find anything on this issue.

I recently had to replace the rear airbags in my 2009 X5 35D, and took it to a mechanic to have the suspension calibrated after I got the job done (not sure why it needed it but it was done). After that visit I started hearing a clunking noise in the rear when going over bumps at low speed. I looked this up and people said it could have been the sway bar end links, however these parts on my car are tight.

So my questions are can these broken parts be the source of this clunking noise? What do the rear radius arms do and is the part shown in my photos the radius arm? How could something like this break? Both sides have the same broken part in the same way.

Thanks for any help,
Aaron