JsonSerializer.Serialize skips children

var hircAsString = JsonSerializer.Serialize((object)selectedNode.Item, new JsonSerializerOptions() { MaxDepth = 32, WriteIndented = true});

{
  "AkBankSourceData": {
    "PluginId": 262145,
    "PluginId_type": 1,
    "PluginId_company": 0,
    "StreamType": 0,
    "akMediaInformation": {
      "SourceId": 378298469,
      "uInMemoryMediaSize": 12089,
      "uSourceBits": 0
    },
    "uSize": 0
  },
  "NodeBaseParams": {
    "NodeInitialFxParams": {
      "bIsOverrideParentFX": 0,
      "bitsFXBypass": 0,
      "FxList": []
    },
    "bOverrideAttachmentParams": 0,
    "OverrideBusId": 0,
    "DirectParentID": 0,
    "byBitVector": 0,
    "NodeInitialParams": {
      "AkPropBundle0": {},
      "AkPropBundle1": {}
    },
    "PositioningParams": {
      "uBitsPositioning": 0,
      "uBits3d": 0,
      "ePathMode": 0,
      "TransitionTime": 0,
      "VertexList": [],
      "PlayListItems": [],
      "Params": []
    },
    "AuxParams": {
      "byBitVector": 0,
      "auxID0": 0,
      "auxID1": 0,
      "auxID2": 0,
      "auxID3": 0,
      "reflectionsAuxBus": 0
    },
    "AdvSettingsParams": {
      "byBitVector": 16,
      "eVirtualQueueBehavior": 1,
      "u16MaxNumInstance": 0,
      "eBelowThresholdBehavior": 1,
      "byBitVector2": 4
    },
    "StateChunk": {
      "StateChunks": [],
      "StateProps": []
    },
    "InitialRTPC": {
      "RTPCList": []
    },
    "eGroupType": 0,
    "ulGroupID": 0,
    "ulDefaultSwitch": 0,
    "bIsContinuousValidation": 0
  },
  "OwnerFile": "wwise\\audio\\simplebnkproject.bnk",
  "IndexInFile": 0,
  "HasError": false,
  "Type": 2,
  "Size": 84,
  "Id": 3990607256
}