I have a Living Atlas layer shared on my portal (not accessible outside my intranet sadly). The layer includes some pre-built raster functions. What I'm trying to do is load the layer into a webmap using the 3.28 ArcGIS JS API and apply a specific raster function to affect the appearance.

Based on my reading here and here, it seems like this should be possible. The layer loads just fine but the raster function is not being applied. It's coming in as the default grey-scale stretch symbology and with no helpful errors in the console to help me along. Can anyone point me in the right direction?
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