Azure DevOps部署AAS模型时多数据源凭证配置报错求助

我有一个包含两个数据源连接的Tabular模型，两个数据源分别连接不同服务器及数据库以获取模型表数据。我在Azure DevOps中创建了发布管道，通过Tabular Database Deployment步骤将model.bim文件部署到Azure Analysis Server。

因为存在两个数据源，我在该步骤中选择了Advanced (multiple connections)类型，必须在Advanced datasource security settings中为每个数据源提供凭证，否则处理模型表时会出现凭证未正确提供的错误。

在该步骤之前，我已配置两个前置任务：一个从Azure Key Vault获取数据，另一个通过Azure CLI任务获取Service Connection详情，Tabular Database Deployment是最终部署步骤。

我在Advanced datasource security settings中尝试了以下JSON配置：

[
  {
    "type": "structured",
    "name": "TEST1",
    "connectionDetails": {
      "protocol": "tds",
      "address": {
        "server": "room1.net",
        "database": "Test_db1"
      },
      "authentication": null,
      "query": null
    },
    "credential": {
      "AuthenticationKind": "UsernamePassword",
      "kind": "SQL",
      "Username": "bla1",
      "EncryptConnection": true,
      "Password": "$(DS1_PASSWORD)"
    }
  },
  {
    "type": "structured",
    "name": "TEST2",
    "connectionDetails": {
      "protocol": "tds",
      "address": {
        "server": "room2.net",
        "database": "Test_db2"
      },
      "authentication": null,
      "query": null
    },
    "credential": {
      "AuthenticationKind": "UsernamePassword",
      "kind": "SQL",
      "Username": "bla2",
      "EncryptConnection": true,
      "Password": "$(DS2_PASSWORD)"
    }
  }
]

但部署时出现以下错误：

Invalid object passed in, ':' or '}' expected.

我尝试了多种方法仍无法解决，无法将存储在Azure Key Vault中的凭证变量传递到部署配置里。我的需求是能够正常处理不同数据源的表，确保Azure DevOps发布管道传递的凭证被正确包含在部署过程中。

附最终部署步骤的完整YAML：

steps:
- task: liprec.vsts-release-aas.deploy-aas-db.deploy-aas-db@1
  displayName: 'blabla1'
  inputs:
    connectedServiceNameSelector: connectedServiceNameARM
    connectedServiceNameARM: 'ppppp'
    aasServer: 'pppppp.net'
    databaseName: 'test11_tabular'
    loginType: spn
    tenantId: '$(tenantId)'
    appId: '$(servicePrincipalId)'
    appKey: '$(servicePrincipalKey)'
    pathToModel: '$(System.DefaultWorkingDirectory)/aa/Model/test11_Tabular/bin/Model.asdatabase'
    partitionDeployment: deploypartitions
    roleDeployment: deployrolesandmembers
    connectionType: advanced
    datasources: |
      [
        {
          "type": "structured",
          "name": "TEST1",
          "connectionDetails": {
            "protocol": "tds",
            "address": {
              "server": "room1.net",
              "database": "Test_db1"
            },
            "authentication": null,
            "query": null
          },
          "credential": {
            "AuthenticationKind": "UsernamePassword",
            "kind": "SQL",
            "Username": "bla1",
            "EncryptConnection": true,
            "Password": "$(DS1_PASSWORD)"
          }
        },
        {
          "type": "structured",
          "name": "TEST2",
          "connectionDetails": {
            "protocol": "tds",
            "address": {
              "server": "room2.net",
              "database": "Test_db2"
            },
            "authentication": null,
            "query": null
          },
          "credential": {
            "AuthenticationKind": "UsernamePassword",
            "kind": "SQL",
            "Username": "bla2",
            "EncryptConnection": true,
            "Password": "$(DS2_PASSWORD)"
          }
        }
      ]
    overwrite: false

内容的提问来源于stack exchange，提问作者Abdio68