Knowing the size of the holes and slot would help.
Hardware stores sell a colored bolt with a flat head which is tightened with an allen wrench. Could you install 4 of these in the back of the TV and hang the TV using the bracket shown? You may need a nut on each bolt so the bolts don't protrude to deep inside the TV case and short out the electrical. Looking online I found the following:
http://www.bing.com/images/search?vi...=13&ajaxhist=0
The bolts are called "furniture bolts" I believe. You would need shorter bolts than the ones shown. The bolts are available in different lengths and dia.