Well, Liam Neeson could be considered a “resource” of the Jedi Council.
No, I’m not talking about the supposed arrogance of the Jedi Council (I still don’t get this whole point, honestly), I’m merely saying maybe at first Windu was just saying that everyone together (he, Qui-Gon, Obi-Wan, Creepy Puppet Yoda, CGI Yoda, unnamed-in-the-movies-but-has-his-own-extralong-Wookieepedia-article Jedi Council Member #10) would solve the mystery, and later he and the rest of the Council were bored and severely procrastinating and Windu said that maybe Obi-Wan and Qui-Gon should go and solve it instead of involving every Jedi or the Council because otherwise there would be no climax involving death and laser swords.