Domain Access and $THEME_URLS in settings.php

I have this function in my settings.php:

$THEME_URLS = array(
array('/optoelectronics','optotemp'),
array('/power-devices','optotemp'),
);
foreach ( $THEME_URLS as $info)
        if ( strpos($_SERVER['REQUEST_URI'],$info[0])===0)
                $conf['theme_default'] = $info[1];

Though I am applying a new theme, these two sections are to stay with the old theme with slight header css modifications. The issue that is I have another European domain which should stay as it is (the old theme) and that site has the same sections.

So, I've duped the old theme, renamed it and installed it, made two templates for these specific sections and used css appropriately.

My thinking is that with optotemp being called instead of the old or new theme, those will be selected thus using css only from optotemp.

However, I'm not sure (and can't really test offline) if that function above will override what the Domain theme settings are for the European site and pull that optotemp theme instead.

My launch last night was not successful due to pulling the old theme for those two sections and css which worked, but then visiting the Euro site, it had all the css edits applied since it was using the old theme.

So I'm trying to tell Drupal, "if the domain is www.euro.com use theme A" and stop there. This is normal behavior with Domain Access domain theme settings. But on the new US site I'm trying to tell Drupal "if the domain is www.us.com use the new theme B, but when on us.com and the url is /optoelectronics use theme optotemp.

I don't want the euro.com/optoelectronics to use the theme optoelectronics.