A group's health state stays in the grey/uninitialized no health information or unknown state when viewed in Squared Up.
To read more about health states for objects see Status Icons.
When you create a group in SCOM it does not by default have a health rollup monitor or any unit monitors, so the health state stays in the grey/uninitialized no health information state.
To show the health of the group members using the group object you will need to add a health rollup monitor.
In SCOM click on the Authoring tab
Expand Management Pack Objects.
Right-click on Monitors, select Create a Monitor and then Dependency Roll Up Monitor.
Give the monitor a suitable name.
The Monitor Target should be your group.
Leave the Parent monitor set to Availability.
Select the same unsealed management pack that your group is in.
Click Next to move on to Monitor Dependency.
Expand Object (Contains Entities), expand Entity Health, and click on Availability.
Click Next, Next, Create.
After you have created a health rollup you may have to wait a minute or two and then your dashboards should show the health for your group.
Here is a blog that provides a very straightforward walkthrough with screenshots:https://sites.google.com/site/scomblogs/journal-blog/monitoringtheavailabilityandhealthofagroupinscom
Alternatively, in order to simplify this process, Tao Yang, MVP, has created a community Management Pack - OpsMgr Group Health Rollup Configuration Task Management Pack - which provides an agent task to create dependency monitors for the selected groups using the OpsMgr SDK.
Full details of that are available here;
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