Hm. Strange, indeed. The only thing, that i could see from your PHPinfo, is that open_basedir is set.
ezPublish sometimes had problems with this earlier, but i don't think, that this is it.
Also, safe_mode is on and i don't know, if this setup is supported with ez3.
I think, safe_mode beeing enabled requires, that the PHP files (index.php and pre_check.php) must be owned by the User, that runs the webserver (apache). But the install wizard should have told you about this.