I hate to side with the MEA mouthpiece, but he used "proved" correctly.
The American Heritage Dictionary:
Proved is the preferred form as past participle. It has proved satisfactory. He has proved his point. The alternate proven is acceptable to only 27 percent of the Usage Panel in such examples. But proven is the more widely employed form as an attributive adjective (used before a noun): a proven record.
Hitlery Clinton most infamously used the word "proven" when she said
that if her husband had had an affair with an intern in the White House that would truly be "extremely serious," but "that will not be proven to be true."The smartest woman in the world was wrong, of course -- both in fact, and in her use of grammar.