I think Joe thought you were using the HTML Content Module for this but it sounds to me like you're using the HTML Fragment Include. Disabling the WYSIWYG isn't going to help at all with the Fragment Include module.
I was able to use the code you shared in a fragment include here but it's not reliable. I originally added it to a site using IE 10 and it was fine but on refresh, I get a message stating the content cannot be displayed in an iFrame and when clicking the link to view it in it's own window I would get a message from Google stating the query was bad. Even when viewing the html file on it's own (outside of mojo), it's not reliable in IE. It's consistently working fine in FireFox.
So, I think this problem is with IE and Google, not mojoPortal.
HTH,
Joe D.