Actually, it's one part desperation combined with two parts stupidity.
The desperation is reasonable, as Team USA has performed poorly in the past few years, but it's just plain stupid to believe that a coach alone will even come close to bridging the giant gap between Team USA and Team Europe.
The coach that turns Team USA around will be the one that works with his players to improve specific skills in which they've shown weakness in Mosconi Cups past. The idea that a coach living overseas will be the one to accomplish this is just plain stupid.
Hence, after tabulating, it's one part desperation and two parts stupidity.
I agree with your first "stupidity," but to be fair we don't know about the second.
But I'll add a third stupidity: Matchroom should have known that Americans have such childish, fragile egos that simply the fact that Ruijsink is European would drive so many of us crazy.