Considering how it's entirely IC for Ajax to get pissed at someone trying to shoehorn in on his fights, and how you did a pretty big faux pas by [i]abandoning your group so you can further unbalance the other group[/i], Ajax's response is over-the-top but justifiable.

You probably could have handled it better than throwing grenades at him and lobbying to get his character punished because your poorly thought-out plan went awry. There's no need to stoop to Ajax's level, after all.