Hi Jason, welcome to SharpTools and the community. After you added the device back in HE, you will have to re-authenticate it to SharpTools by going to the user page -> Manage Connections -> Hubitat, and follow the auth process like you did before.
For the Ecobee sensor, can you see the sensor in the device list at all? If not, make sure you have authorize it to SharpTools. Once you add the sensor to your dashboard, you can change the layout to “hero attribute” layout and configure what/how you want to display the readings.
Here is the KB article about the “hero attribute” layout for more details.