Take a look around the faying surfaces. Almost no brazing material seeped into where it was supposed to. It looks as if the bottom peg was yanked out a bit during your mechanical test due to the small variation on coloring. A tiny amount of brazing material entered there at the corner but was ripped apart and you can see the other half of what is left of it on the opposite corner on the other half of the part.
I used to radiograph tons of brazed parts on the east coast. There is something wrong with your process and UT or RT will not tell you what it is.They can tell you where the voids are but not what caused them or how to fix them.
That part also looks like it would take awhile to set up a decent technique with radiography too. Shooting it eliptical like a pipe weld won't be that great because the faying surface is so thin and would resemble lack of side wall fusion which radiography has a hard time picking up. Then if you need to determine the amount of voids in the faying surfaces with those 2 pegs you run into more wore work. Before you send it out for all kinds of fancy testing make sure you can't pull it apart first.
Check out these 2 companies that do dip brazing on stuff that goes into space. They braze tons of stuff and do big percentages of a lot with radiography. As long as you aren't in competition with them their engineers might help you out. They are on the East coast but they might be able to help.
http://www.contmicro.com/index.asphttp://www.mdllab.com/