Did you look in the Services Flow diagram view, select the 'unmonitored' entity and on the right there's some information about the selected entity. Be sure to explore the Infrastructure tab on the right, after you've selected an entity on the left.
Let us know if this helps.
Go to Transactions & Services (left Menu) -> Unmonitored Hosts -> Response Time
Then scroll down and a list of these hosts will be displayed.
Is it possible that there are calls from hosts in one Env to hosts in another Env? Environments separate completely. Another option if there really are calls across Environments to instead use Management Zones, which if you have access to both zones you'll be able to see data across Zones. I'm just not sure this is really what you want however.
Let me know if you find the list of 'unmonitored hosts'.
Feeling intensely stupid. Left-menu > Transactions & Services. Column 2 shows next-level options grouped under headings: State, Scope and Usage, Service Type, Service Technology, Request Attribute and Tags. None of these groups have an "Unmonitored Hosts" option. Nor can I find the version of DynaTrace we're running internally, in case I'm having an "old UI" problem.
When viewing the Transactions & Services screen, on the right side, scroll down thru the list of Services and you should see a row with "Requests to Unmonitored Hosts". Drill into that, then into "Response Time" Infographic.
Let us know.