CKEditor “insertHtml” is working for FF but need a solution for IE8+

I want to append a new HTML tag in ckeditor content. 
bellow code is working fine for FF but its not inserting the tag in IE8.

`setData()` will not work for me. I think it's replacing all content with the new HTML tag.

    var idVal = 123; 
    var attrib2Val = "some value";
    var NewHtmlTag = "<CustTag id=\"c" + idVal + "\" attrib2=\"" + attrib2Val + "\"></CustTag> some extra text ";

    EditorInstance.insertHtml(NewHtmlTag);
    
I need a solution for IE8+.