D3Publisher has a US branch now, they could do it if they wanted... but D3 Publisher is acting like they want to become a regular publisher though, so maybe their US branch will turn their nose at this.
... Conspiracy Entertainment should do it!
Simple Series games have been localized by various clown meat publishers for Europe since the original PlayStation, but since D3 set up their own European HQ and started doing some of the PS2 ones themselves, every other publisher has stopped. So I guess D3's all NAAWWWW now, nobody else can touch them, even though they're slacking off pretty hardcore lately.
The Simple games never existed in America on PSone or PS2 because Sony blocked them (though I believe a whopping three or so managed to slip through). One of the DS games made it over (Break 'Em All ie;
Simple DS Series Vol. 4: The Block Kuzushi) by D3 America, but after that they seemed to get all pissy about localizing anymore and started focusing on crappy cartoon licensed games. Maybe they won't let anyone else touch them much like D3 Europe.

Because I'm sure other publishers would have given these a crack by now, the Wii Simple Series have been turning out surprisingly decent so far, and there's a handful of good DS ones (like the one this thread is based on~).
(D3 America DID try and get Oneechanbara Vortex for 360 out though, shortly after Earth Defence Force 2017, but it was rejected... perhaps they'll try again with the Wii version since Nintendo's much more relaxed!)