The sitemap has a particular way of setting addressable views. Unfortunately your approach is supported for everything but the sitemap (source link at bottom).
Display a View in the Application Navigation using the Site Map
When you customize the application navigation using the site map, do not use the view URL that you copied from the application using the steps in Copy the URL for a View to set as the URL. That URL displays a page that includes the ribbon and produces undesirable results if used in a
<SubArea> (SiteMap)
Url attribute.To display a list of entity records within the application for a SubArea set the Entity attribute value. This displays the default view for that entity and provides the correct title and icon.
However, if you want to have a SubArea element that uses a specific initial default view, use the following Url pattern.
XML:
Url=“/_root/homepage.aspx?etn=<entity logical name >&viewid=%7b<GUID value of view id>%7d”