Since you only have one extra row of data you would have to use a subreport to 'reuse' that row for any employee that did not have rows per week.
If this concept works for your overall needs here is one way to approach it.
Create the main report on all workers that any rows during your time period.create a group per worker record.
make a subreport kinking from main report employee id to the subreport employeeid.
alter your subreport select statement to also include the 'dummy' employee records.
group on the week field.
you will see two records in the group if the employee was present and 1 if they were not.
Create a Running Total.
Field to summarize = hours field
type=SUM
evaluate on change of group
reset to never.
place in report footer.
this should sum the corrected hours.
Change the report format to how you want it to look.
You may need to pass date params from the main to the sub reports as well.
Does this do what you need.