Sorry Nick I was looking at the wrong server. Here is correct service json
{"currentVersion":10.41,"serviceDescription":"Service for HFD CIFOA supervision and Audit","hasVersionedData":false,"supportsDisconnectedEditing":false,"syncEnabled":true,"syncCapabilities":{"supportsRegisteringExistingData":true,"supportsSyncDirectionControl":true,"supportsPerLayerSync":true,"supportsPerReplicaSync":false,"supportsRollbackOnFailure":false,"supportsAsync":true,"supportsAttachmentsSyncDirection":true,"supportsSyncModelNone":true},"supportedQueryFormats":"JSON, AMF","maxRecordCount":10000,"capabilities":"Create,Delete,Extract,Query,Sync,Update,Uploads,Editing","description":"","copyrightText":"RobK","spatialReference":{"wkid":3308,"latestWkid":3308},"initialExtent":{"xmin":9405747.734332878,"ymin":4235472.443658285,"xmax":9409041.803421017,"ymax":4236913.102789603,"spatialReference":{"wkid":3308,"latestWkid":3308}},"fullExtent":{"xmin":0,"ymin":-3622637.5840000007,"xmax":1.03139531981E7,"ymax":5858939.346900001,"spatialReference":{"wkid":3308,"latestWkid":3308}},"allowGeometryUpdates":true,"supportsApplyEditsWithGlobalIds":true,"units":"esriMeters","documentInfo":{"Title":"","Author":"","Comments":"Testing FC for IFOA builds","Subject":"Test Build For mobile IFOA edit feature","Category":"","Keywords":"FCNSW IFOA HFD"},"layers":[{"id":0,"name":"CIFOAPlanPoly"},{"id":1,"name":"MassMovementMapping"},{"id":2,"name":"HFDHarvestPlanAreaGross"},{"id":3,"name":"HFDWildlifeHabitatClump"},{"id":4,"name":"HFDTreeRetentionClump"},{"id":5,"name":"HFDHarvestPlanBNA"},{"id":6,"name":"HFDHarvestPoly"},{"id":7,"name":"HFDPatch"},{"id":8,"name":"HFDHabitatCoastal"},{"id":9,"name":"HFD_OSA"},{"id":10,"name":"HFDTreesCoastal"},{"id":11,"name":"HFDHarvestBA"},{"id":12,"name":"HFDTraverse"},{"id":13,"name":"CIFOAPlanLines"},{"id":14,"name":"CIFOAPlanPoints"},{"id":15,"name":"HFDCrossing"},{"id":16,"name":"HFD_Dump"},{"id":17,"name":"HFD_IncidentalFF"},{"id":18,"name":"HFDContractorNote"},{"id":19,"name":"QAATree"},{"id":20,"name":"QAADump"},{"id":21,"name":"QAASnigDrainage"},{"id":22,"name":"QAASnigCrossing"},{"id":23,"name":"QAAPoint"},{"id":24,"name":"QAAIncursion"},{"id":25,"name":"QAAEvent"},{"id":26,"name":"QAABoundaryTransect"},{"id":27,"name":"CIFOACompliance"},{"id":28,"name":"HFDNote"},{"id":29,"name":"Hazard"}],"tables":[],"enableZDefaults":false}
Hmm. That service JSON doesn't have a subtypes attribute. Contrast with this version that I found: http://52.64.246.55/arcgis/rest/services/EPA/HFDRegulationRef/MapServer/11?f=json
That service is 10.6.1 compared to your 10.4.1. I'm asking around to see what this means (this is an area of the spec I'm not very familiar with). But it matches what we're seeing in Runtime and if I open that 10.6.1 layer in Runtime I do see the subtypes parsed properly.
Thanks Nick. Looks like ArcGIS Server 10.4.1 does not support subtypes...