You should see all the same functionality, you're just viewing it from within the dashboard. I just tested on my end and can use the summary panel for any of the WLB items from within the dashboard I pulled the WLB into. Try going to the dashboard setting and increasing the heigh to 1000 instead of the default 500 when adding an external page. If that still doesn't work and you cannot use the summary panel at all then I'd submit a Support ticket bc that sounds like a bug.
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