Can you please tell me what's the datatype of MainMenuBean.organizations property ?
Assuming organiztions is list.
You can solve this as below.
1. Creae pojo class which contains the properties for orgTypeDesc(
String), orgList(SelectItem List) and orgSelected(String).
2. Create objects and set the values from organizations list(the list which you are passing to datatable) and create Arraylist of the newly created class.
3. Use the updated arraylist for iterating the datatable.
4. Bind the select many list box value with orgSelected property of the newly created pojo class.
5. After form submit selected value in select manylist box will set to orgSelected property.
6. Iterate the updated arraylist to get to know the orgSelected property for each row.
Please let me know if you have any confusion.