https://gis3.gisworkshop.com/arcgis/rest/services/City_of_Tecumseh_NE_MGMT
https://gis3.gisworkshop.com/arcgis/rest/services/City_of_Tecumseh_NE_MGMTThis is a folder inside the services directory, not the server root. Trim back to /rest/services to connect to the whole server.
The Services Directory is turned off here, so the browsable folder listing will not load. Use ?f=pjson to read the service list as JSON.