retrieving storage value always results in null

This seems like something that should be easy to solve but I always get a null value when trying to getValue some storage data. I want to make 2 customizable fields in the app settings. These are the properties, settings, and string.xml files, with 2 fields:

<properties>
    <property id="Lat_u" type="float">38.8551</property>
    <property id="Lon_u" type="float">-94.8001</property>
</properties>

<settings>

	<setting propertyKey="@Properties.Lat_u" title="@Strings.Latitude">
		<settingConfig type="numeric" required="true"/>
	</setting>

	<setting propertyKey="@Properties.Lon_u" title="@Strings.Longitude">
		<settingConfig type="numeric" required="true"/>
	</setting>
	
</settings>

<strings>
    <string id="AppName">Test</string>
    <string id="Latitude">Latitude</string>
    <string id="Longitude">Longitude</string>
</strings>

Then I have a background event, registered in the getInitialView() of the app, that tries to load the data like so:

using Toybox.Application.Storage;

...

(:background)
class BgbgServiceDelegate extends Toybox.System.ServiceDelegate {
	
	var APIKEY = ...
	var home_lat = Storage.getValue("Lat_u");
	var home_lon = Storage.getValue("Lon_u");
	
function onTemporalEvent() {
    
    ...
    Sys.println(home_lat);
    
    ...
}

I use the simulator to launch a background event. Before doing so I go to the App Settings Editor in Eclipse, select my app, and send the (unchanged) settings (I don't know if that is actually necessary given that I have defined some default values). Both fields are null when I try to load/print them from the app initialize() as well. Testing for the 645M.