Решением был раздел миссии в web.config.
<system.data>
<DbProviderFactories>
<remove invariant="Oracle.ManagedDataAccess.Client" />
<add name="ODP.NET, Managed Driver" invariant="Oracle.ManagedDataAccess.Client" description="Oracle Data Provider for .NET, Managed Driver" type="Oracle.ManagedDataAccess.Client.OracleClientFactory, Oracle.ManagedDataAccess, Version=4.122.1.0, Culture=neutral, PublicKeyToken=89b483f429c47342" />
</DbProviderFactories>
</system.data>
<oracle.manageddataaccess.client>
<version number="*">
<dataSources>
<dataSource alias="SampleDataSource" descriptor="(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=localhost)(PORT=1521))(CONNECT_DATA=(SERVICE_NAME=ORCL))) " />
</dataSources>
</version>
</oracle.manageddataaccess.client>