I'm under the impression that Selenium IDE is a firefox plugin.
Also, generally people don't mix QTP and selenium. If you need to do some native automation, you normally would just write a test hook and automate it using code instead of a heavyweight tool like QTP. Only reason I can think of needing both QTP and Selenium is if you want to automate a plugin that runs cross browser, and you have no access/support for adding test hooks.
But if you really have to execute a selenium script from QTP, I think the approach you're taking is the hard way. What you want to do is export the selenium script to a say a jUnit or TestNG unittest. Then compile that into a stand alone JAR. Then all QTP needs to do is launch a command line program to start the test.