You might also need to add:
Set mgr.IQN=SchemaName_"."_$Translate(TableName,".",$c(2))

Great for dealing with errors as they happen - before they get out of hand!

It looks like you are able to fix this error. Just in case anyone else comes across this error in the future, it means that the data has not yet been built for the element that is being referred to. In this example, that element is [Measures].[AvgTime]. By running the task, the following line was executed:

set tCubeRebuild = ##class(%DeepSee.Utils).%BuildCube("Operational Analytics")

This performed a full build of the cube, so the Measure that was referenced in the error and all other elements in the cube were built