Is it possible to add a User Input field to the report?

We are using a modified version of a WO Estimate Report in ViewPoint and would like the ability to manually type in the customer's phone and email once the report has been generated if it is missing from their information at the start. We know the info can be added in the background so it will populate on the report, but they don't know it is missing until they generate the report and stopping at that point would interrupt their workflow when timing is critical.

Is it possible to add a User Input field to the report for populating after the report has been generated?

My thoughts were to overlay the user input field and field from the database but suppress the database field when blank so only the user input would appear. I didn't want it to be done as a parameter field because I want to avoid unnecessary filtering and they will not know if the information is missing at the beginning.