I have modified the WIT To add the estimated work on scrum task template but it's the values on not roll-up on the PBI.
Could you please provide some insight to calculate the values? Does it possible on SCRUM?
If your team project was created using the Visual Studio Scrum process template, only Remaining Work is defined in the task by default. Even though you have customized the WIT by yourself, however this will not roll up on PBI by TFS. As you have seen the Rollup requirements.
It's also reflect in report area and cube:
The cube contains all the fields of all your collections on the TFS server. A project created with the Agile or CMMI process template will have that field and it will create the field in the cube. Scrum projects don't have that field, so if your project is created with the Scrum process template your Task work item does not have that field and the value in the cube will be blank.
Actually, Scrum isn't interested in the original estimate, tracking "spent time" is not really in line the philosophy of Scrum. Suggest you stay away from tasks-in-hours marrying up to people-in-hours with using Scrum template.
Highly recommend you first go through the discussion in below threads especially Jesse's post, then consider if use estimated work in scrum: